!!The Main Trio

->Voiced by: Greg Eagles

The GrimReaper who is fated to be Billy and Mandy's "best friend" forever after losing a limbo contest to them.
* AbusiveParents: Depending on the episode. His mom always complains about his lack of enthusiasm for his job and his dad would never talk to him and always listened to country music.
* AcquaintedWithEmergencyServices: He has this relationship with the nursing staffs at the retirement homes when he comes for the elderly residents, as shown in Season 5 "Home of the Ancients".
-->'''Gloria''': Hi, Grim.\\
'''Grim''': S'up, Gloria.\\
'''Gloria''': Aw. Are you here for Mr. Silverman?\\
'''Grim''': No. That's next week.
* {{Adorkable}}: Despite being the shadow of death itself, he has his fair share of adorably dorky moments throughout the series, especially during the flashback in ''Wrath of the Spider Queen''.
* AffablyEvil: Is remarkably polite when he isn't putting his scythe to work or getting bossed around by the title characters.
* TheAgeless: Looks no different from how he looked centuries ago due to being a living skeleton with no skin.
* AndIMustScream: Eternally a prisoner to Billy and Mandy. Can't violate his contract with them or else he'd ''then'' spend an eternity in the Underworld Prison.
* AntiHero: He's an anti-hero only when a greater evil threatens the world or Billy and Mandy.
* AntiVillain: He's not TheGrimReaper by choice, but because he was forced by his parents to be (though this does flip-flop around. One special revealed being a Reaper was being voted by your fellow students in ''high school''). He's also constantly getting his weight thrown around by Billy and Mandy. In fact, if he didn't suffer these two circumstances, he almost wouldn't be villainous at all. That's proven, as he's a fairly nice guy, whenever he's not on his job to take someone's life.
* BadassBoast:
** "You don't know who you're messing with, man! I am TheGrimReaper!"
** He had another good one in "Grim vs. Mom".
-->'''Grim:''' Foolish mortal! I don't think you know who I am. Let me give you a hint! (''Magics up his scythe'')
* BadassLongcoat: As expected of the Grim Reaper.
* BadlyBatteredBabysitter: His general function in the show is to suffer from having to look after Billy and Mandy.
* BewareTheNiceOnes: He's pretty nice when not reaping, though it has been made clear on several occasions that despite his attitude and butt monkey status to Billy and Mandy, he is not one to be trifled with when his patience is at an end. Just ask Jack O' Lantern.
* ButtMonkey: A lot less than Billy, but he has his moments of humiliation when he's near Mandy or a rival.
* CantStandThemCantLiveWithoutThem: On several occasions when he is given the opportunity to be free of Billy and Mandy, he finds being without them even worse than being stuck with them.
* ConditionedToAcceptHorror: In ''Big Boogey Adventure'', he's able to get Horror's Hand, which requires someone to face their worst fears, because his worst fear is [[WithFriendsLikeThese having to spend time with Billy and Mandy]], which he has to do every day anyway.
* CrouchingMoronHiddenBadass: While being pushed around by Billy and Mandy, he still knows how to get the job done as the reaper and kick a mean can of ass. He can be legitimately frightening when he wants to be.
* DarkIsNotEvil: He may be a skeleton in a black cloak who collects people's souls when they die, but at the very least he's nowhere as evil as [[VillainProtagonist Mandy]].
* DeadpanSnarker: He makes a lot of death jokes and underworld puns. He's also prone to making cutting remarks about Billy's idiocy.
* DemBones: Grim is a living skeleton under his robes. More than once, the other two protagonists have been known to take him apart in order to carry him in a backpack or other small container.
* TheDevilIsALoser: He's portrayed as an unpopular sissy even before he becomes the kids' servant. In his past, it is shown he didn't even ''want'' to be the Grim Reaper, it was just something his parents forced him to do. He took up his role in full swing in order to terrify and get revenge on those who bullied him at school.
* DimensionalCutter: He can open up portals to the underworld or other dimensions by simply ripping thin air with his scythe.
* DoesNotLikeShoes: He is rarely shown wearing shoes.
* DontFearTheReaper: Downplayed; he's an AffablyEvil PunchClockVillain who can be scary when he's ''reaping'' somebody but is otherwise a nice guy.
* DubNameChange: From Grim Reaper to "Puro Hueso" (Pure Bone) in the Latin American version, mostly referred as Huesos (Bones) by the cast. He is also nicknamed "Huesitos" (Little Bones) affectionately by Billy.
* EvilHasABadSenseOfHumor: Even Mandy is sometimes taken aback by the macabre horror Grim finds delightful.
* FourTemperamentEnsemble: The Melancholic. He's overly critical of Billy, gets angry when the two kids don't listen to him, and is often emotionally insecure.
* GrumpyBear: Downplayed. He's only grumpy when he's in a bad mood.
* GlowingEyesOfDoom: Several times when he gets absolutely enraged, his eyes glow.
* TheGrimReaper: Obviously, he's the personification of death.
* HeroicComedicSociopath: Death amuses him, like when he laughs during a show when a patient flatlines, something that even Mandy looked sad to see.
* HeelFaceTurn: After making the deal with Billy & Mandy, he's more or less a good guy.
* HisNameReallyIsBarkeep: It is implied on several occasions that his given name actually is Grim and that his last name is Reaper.
* HotBlooded: Pretty often, he's shown to be quite emotional.
* HumanityEnsues: In "Night of the Living Grim", he becomes a mortal human after succumbing to Encroaching Doom Syndrome. [[StatusQuoIsGod The episode ends with him becoming a skeleton again]].
* HypercompetentSidekick: The reason why Mandy wants to keep him and ditch Billy is because he's more intelligent and reasonable.
* HypocriticalHeartwarming: Quite a few times when it comes to Billy and Mandy, he saves them from someone trying to do something to them that he only finds okay when he's doing it to them. One of the best examples was in "Scythe 2.0":
--> '''Grim:''' You keep away from those kids! If ''anyone'' is going to have their heads, it's going to be ''me''!
* HypocriticalHumor: He often bluntly points out how stupid Billy is. And yet, it tended to hurt his feelings when Billy called him stupid for criticizing his favorite show.
* IAmBigBoned: A variation in the comics. Grim isn't thin. He's "delicately boned".
* ICallItVera: In "The Taking Tree", we learn that he calls his scythe "Jodie".
* TheKirk: More or less trying to survive being stuck with two insufferable children.
* KissedKeepsake: After Eris is tricked into kissing Grim, he says he never washed his face before and won't start doing it now.
* MistakenForPedophile: Heavily implied in "Duck!", where he gets arrested for removing his cloak in front of children while shouting "Look at my body!" in an attempt to explain to the children that he is incapable of passing gas.
* MultipleChoicePast: His many flashbacks to his past seem pretty unreliable. Possibly parodied at one point as well--two of his proposed backstories ''directly contradict each other'' in such a way that would be impossible to HandWave, {{Retcon}} or even ignore outright[[note]]in one, he wanted to be a singer but his dad wanted him to be the Grim Reaper, while in the other his dad wanted him to sing while he wanted to become the Grim Reaper[[/note]].
* NoRespectGuy: Even in the underworld, he gets no respect for his many duties as Reaper.
* NotSoAboveItAll: He tends to get swept up in Billy and Mandy's antics pretty regularly.
* OddFriendship:
** He actually manages to bond with Billy quite a bit.
** He and Mandy share a dark and macabre sense of humor, helping them to get along at times.
* OnlySaneMan: Despite being an all-powerful supernatural being hanging around a suburban neighborhood, he is much more grounded and stable than every other character.
* ParentalSubstitute: For Billy. Both of his parents are alive, but his dad is an idiot and his mom is a psychopath, so Billy respects and admires Grim much more than either of them. He cooks and cleans for him and is quite fussy about him doing his homework, but also provides an actually respectful adult male figure in his life. Billy even says in one episode that Grim is his idol, and Grim in turn occasionally displays outright fatherly affection for him.
* PhysicalGod: He's the Grim Reaper, after all, so of course he would possess immortality and great powers.
* PunchClockVillain: As he himself once stated, he's just doing his job. He's also very friendly when not doing so. After all he rarely reaps people's souls before it is their time anyway.
* RageBreakingPoint: Normally subservient and kind even when being bossed around, he ''does'' have limits though; when he's finally had enough and loses it, even Mandy herself often won't mess with him.
* RealityWarper: With his scythe, he can cause all sorts of things to happen.
* ReallySevenHundredYearsOld: He was a little kid during the Stone Age.
* RedAndBlackAndEvilAllOver: His BlackCloak is red on the inside.
* ScaryBlackMan: His voice actor is black.
* ScreamsLikeALittleGirl: Depends on the episode, but he'll quite often scream in a high-pitched and feminine voice when he's scared.
* ShipperOnDeck: He teasingly ships Billy and Mandy occasionally. In "The Bubble with Billy", he even tries to get Mandy to flirt with Billy to get him to cough up the supernatural gum he swallowed.
* SinisterScythe: His scythe can do just about anything...except whack the weeds in Skarr's garden.
* SociopathicHero: He dosen't like conversing with humans, much less saving them.
* TragicVillain: PlayedForLaughs. He didn't become TheGrimReaper by choice, but because his parents wanted him to... [[MultipleChoicePast sometimes]]. Afterwards, he became a PersonOfMassDestruction. He also softens after the deal with Billy and Mandy.
* TallDarkAndSnarky: He is really tall, wears a black cloak, and isn't above making snide remarks toward Billy and Mandy.
* TooDumbToLive: If he never wagered his own freedom, he wouldn't have to put up with Billy and Mandy. The only thing he would've lost would've been an opportunity to collect a hamster's soul.
* UnexplainedAccent: Grim's Jamaican accent. His grandmother also has one, and has a Jamaican look to her to boot.
* VillainProtagonist: A surprisingly downplayed example, since he shows his evil side sporadically and often (but not always) after being provoked.
* VillainsOutShopping: Whenever he isn't ordered to kill someone, he lives a perfectly normal life.
* WellDoneSonGuy: While his backstory is a bit fluid, "Dad Day Afternoon" presents him as this, desperate to earn the approval of a father who loved country rock music more than him.
* WillfullyWeak: Deliberately avoids abusing his powers to prevent causing problems. Unfortunately for him, that's exactly what Billy and Mandy end up doing.
* WouldHurtAChild: He's been shown planning ways of escaping his deal with Billy and Mandy, typically by killing them in unusual ways.

->Voiced by: Creator/RichardStevenHorvitz

A dim-witted boy who frequently causes problems due to his idiocy. Nonetheless, he's usually the most innocent and happy-go-lucky of the trio.
* {{Abusive Parent|s}}: To his "son", the giant spider, Jeff. (Semi-justified in that Billy is extremely stupid and has an irrational fear of spiders) Billy tries his best to squish Jeff including sending an exterminator to crush him beneath a huge cowboy boot, throwing furniture onto him, and cutting the brake cables in his car.
* AcquaintedWithEmergencyServices: In Season 2 "Educating Grim", when Billy tries to race Grim and Mandy to school, he immediately runs into the school's front sign. Cue Nurse Penbroke walking outside hold first-aid kits looking annoyed. After Billy and Mandy leave school, Billy is already covered in bandages and walking with a crutch. When Nurse Penbroke [[StepfordSmiler happily]] waits outside for Billy, he tells her he's done for today and then she releases an exhausted sigh.
-->'''Nurse Penbroke''': Oh, Billy.\\
'''Billy''': ''(cheerfully)'' Hi, Nurse Penbroke. I can't feel my legs.
* {{Adorkable}}: He's so dumb and stupid it's adorable.
* AllLovingHero: Unless you're a spider or a clown, in which case he'll try to murder you, Billy is surprisingly adept at befriending pretty much everybody, and has succeeded in ending conflicts nonviolently several times.
* AmbiguousDisorder: It's fairly obvious that Billy has genuine mental problems in addition to being extremely stupid, as shown by his bouts of psychotic, murderous rage. He may have inherited this from his mother.
* AmbiguouslyJewish: His family apparently celebrates Hanukkah in addition to Christmas, though the way he says it makes it sound like an excuse to get more presents.
* AnnoyingLaugh: He quite often lets out a ridiculous-sounding laugh.
* ArsonMurderAndJaywalking: Billy's three greatest fears are spiders, clowns, and the mailman, with the greatest fear of them all being a spider/clown/mailman hybrid.
* AsskickingEqualsAuthority: In ''A Kick in the Asgard'', he was such a good fighter that even the likes of Thor and Odin feared him, and is revealed to have became the ruler of Asgard in TheStinger of the episode.
* AxCrazy: The disorder thing? Well it can get pretty severe for a clown or a spider (for daring to be different) or for everyone if Billy is in a destructive and hyperactive mood (which he pretty much is all the time) and wields a hammer.
* BewareTheSillyOnes: Billy is often the dumbest character on the show, but he has been shown to have bouts of psychotic rage that manage to scare even Mandy.
* BlackBeadEyes: One of the few characters on the show who has eyes represented as black beads.
* BrattyHalfPint: He can sometimes become an obnoxious pest.
* BumblingSidekick: While he has moments of surprising insight or competence, he generally functions as a dim-witted lackey to either Grim or Mandy.
* ButtMonkey: He gets a lot of physical abuse.
* ChaoticStupid: When Billy takes Mandy's raw nerve, he gleefully abuses Grim, implying that a lack of courage was the only thing that stopped him from doing so before (unless the nerve also influenced his overall disposition since it was ''Mandy's''). He also has an "inner frat boy" that advises him to beat the crap out of anything he doesn't understand.
* CheerfulChild: He rarely has outbursts of rage, but when he does, his happy attitude goes away really fast.
* ChildhoodFriends: He's known Mandy since they were toddlers.
* {{Cloudcuckoolander}}: He will spout stuff that makes no sense except to him and maybe Irwin.
* CordonBleughChef: In an early episode he dreamed that he made cookie dough out of assorted junk food, then ate it raw because [[NoodleIncident he wasn't allowed to use the oven anymore]]. He also apparently eats his cereal with chili and makes his waffles with pickles. One episode has him simply put a ''live turtle'' between two pieces of bread and proudly proclaim "Now that's-a what I call a sandwich!".
* CrouchingMoronHiddenBadass:
** He was able to take on an entire alien fleet by himself, and even [[PhysicalGod Grim]] and [[TinyTyrannicalGirl Mandy]] run from him in fear when he's angry. He's a moron, but he's also very competent badass when he wants to be.
** In "Secret Snake Club", he actually becomes a CIA agent, tracking down a fugitive and exposing [[spoiler: Irwin's plans with the macrame club]].
** He singlehandedly defeated all of Asgard, Odin and the rest of the pantheon included, and he did it with a smile on his face the entire time.
** He also tried to help Hoss Delgado fight a group of zombies with nothing but a stick. Keyword tried, but he survived unscathed.
** His scheme to steal Mandy's raw nerve was remarkably clever for him: he got Grim's cooperation by pointing out that a cowardly Mandy would be unable to bully him, and got the nerve to allow him to swallow it by bribing it with a burrito that happened to be a combo of its two favorite flavors.
* TheDitz: His IQ is [[ExaggeratedTrope -5]], being outperformed in the test by a shovel and two candy bracelets (they got a positive 17).
* DropTheHammer: His WeaponOfChoice is a war hammer, which he is surprisingly skilled at wielding.
* DumbassHasAPoint: Very commonly chimes in to point out the flawed logic in Mandy or Grim's thinking, only to be dismissed as an idiot.
* DumbIsGood: Played with. While his idiocy gives him a childish innocence that allows him to befriend even the most horrible monsters and act unambiguously heroic much more frequently than the other two, [[ChaoticStupid his complete lack of self control and extremely destructive tendencies]] lead him to be arguably the ''most'' dangerous of the three.
* EveryoneHasStandards: Even he thinks Fred Fredburger is annoying.
* ExtremeOmnivore: He enjoys eating boogers, toenail clippings, and (it's heavily implied) cat and dog poo, the last of which he actually uses as steak sauce.
* FieryRedhead: He has red hair and can get pretty frightening when he's angry.
* FluffyTamer: His specialty is befriending supernatural horrors that help the trio out in a pinch.
* FourTemperamentEnsemble: The Sanguine. He's often overly optimistic, good-natured, and will frequently help people that he knows are having problems.
* FriendToAllLivingThings: Although in the case of spiders, he doesn't love them back.
* FutureBadass: In the Big Boogey Adventure. Most notably, in the five minutes of screentime he gets, he almost never says or does a single dumb thing. In fact, he somehow managed to time travel back in time without the use of a nearby inoperable Time Gate. And this is [[TheDitz Billy]] we're talking about. It makes one wonder what did Mandy do to make Billy become this way... Not a dumb thing apart from his last words
-->[[spoiler:'''Billy''': I should have known it was you all along]].
* GagNose: Has a bulbous pink nose that is often bruised or even knocked off his face.
* {{Gasshole}}. Lampshaded by his mom, his first words were in fact gas attacks.
* HeManWomanHater: He insists that Mandy and other girls not be allowed on his baseball team... despite them soundly being better at it than he is. Even having Mindy outperform his team didn't change Billy's mind. Leading to Mandy and Grim discussing whether they should hang lampshade or not. They decide [[TheDitz Billy]] is not worth that trouble.
* HiddenDepths:
** He is shown to dance well, defeat multiple enemies in combat - sometimes without even touching them - and is prone to simple-minded wisdom that actually make a whole lot of sense.
** He's also occasionally surprisingly eloquent for an idiot.
** Despite his immense stupidity, he's perfectly literate.
* IdiotHero: Far more traditionally heroic than [[TokenEvilTeammate Mandy]] and [[AffablyEvil Grim]], but also much more idiotic and twice as destructive.
* ImprobablyLowIQ: -5. Again, a shovel and two candy bracelets are smarter than he is.
* InformedJudaism: The Christmas episode states he's Jewish, but it's never brought up again.
* InnocentlyInsensitive: Whenever he insults Grim, it's mostly when he's acting as Mandy's parrot. On his own, he usually speaks highly of Grim, but also acts like a spoiled and bratty kid.
* IronButtmonkey: Suffers a lot of horrific injuries he somehow recovers from to the point that he could be considered TheChewToy of the show.
* JerkassBall: As with Mandy, Billy has his moments of being insensitive and rude, too.
* JerkassHasAPoint: In "Wrath of the Spider Queen" Billy delivers a massive KickTheDog [[TheReasonYouSuckSpeech speech]] to Jeff where he tries to convey just how much he hates the spider. It was incredibly excessive compared to what triggered it but Billy did raise the point that somehow Jeff ''still'' hadn't figured out the depths of just how much Billy hates spiders.
* JerkWithAHeartOfGold: He's somewhat insensitive and unempathetic but he does have his kind moments.
* {{Keet}}: He's always excited.
* KindheartedSimpleton: Downplayed, while he causes a lot of trouble, it's more often out of his stupidity rather than malice. He generally comes off as well-intentioned and kind.
* LackOfEmpathy: Especially apparent when interacting with his "son", Jeff, not noticing or caring that Jeff loves him and only wants his love to be reciprocated.
* LethallyStupid: ''Everything'' Billy does within the show will inevitably result in mass destruction and chaos, especially when magical artifacts like Grim's scythe are involved.
* LikeParentLikeChild: He's both stupid (like his father) and mentally unstable (like his mother).
* MadeOfIron: He has suffered many injuries throughout the show's run (several of which result in his skin being torn open) and absolutely none of them were permanent. A few of his injuries involve ''having his entire face being blown or torn off''!
* MajorInjuryUnderreaction: Most of the amusing injuries he sustains, he makes little to no reaction to any of them, which isn't really much of a surprise since he's probably too stupid to realize he got injured.
* MeaningfulName: His name means "desire".
* TheMentallyDisturbed: He does the unusual combo of being both moronic and completely insane.
* MoralityPet:
** For [[AntiHero Mandy]]. When she's not bullying him or helping him for her own personal gain, she treats him as a scolding mother would treat her son.
** He's also one to [[SociopathicHero Grim]], who seems almost affectionate towards him at times.
** He's one to [[spoiler: [[AntiVillain Mrs. Claus]] in the ChristmasEpisode, after apparently being the only person in centuries to offer her any help with her multiple duties at the North Pole (without messing up). In fact, Billy's the one who stops her from taking over the world by appealing to her humanity, and by turning Santa back to normal and getting him to apologize for dumping all the work on her.]]
* TheMcCoy: Stupid and impulsive.
* NeverMyFault: In "Billy and Mandy's Jacked-Up Halloween", he indirectly causes all the conflict because he borrowed Grim's scythe, but blatantly shirks responsibility after Jack O'Lantern is defeated and Grim gets his scythe back.
-->'''Billy''': You know, Grim, none of this would have happened if you didn't loan me the scythe in the first place.
* ObliviouslyEvil: Sure he "abuses" his "son" Jeff despite the latter's attempts to flatter him, but that's only because Billy has irrational and psychotic arachnophobia. ''Underfist'' reveals that this was the result of [[spoiler: the true antagonist dangling spiders in front of Billy when Bill was a baby ForTheEvulz]].
* OddFriendship: He's a complete moron whose two closest friends are an obscenely dark and anarchistic girl and the humanoid personification of death.
* OneManArmy: He's occasionally shown to be almost disturbingly powerful when angry, to the point where even Mandy is terrified of him.
* OnlyFriend: He appears to be the only person Mandy actively hangs out with.
* PinkGirlBlueBoy: The blue boy to Mandy's pink girl. He wears blue jeans and a shirt with a blue stripe on it, while Mandy wears a pink dress.
* ThePollyanna: One episode has Billy chronicle his daily experience. It's surprisingly depressing. Not that he notices. His life is honestly pretty horrible, but he remains a blissfully oblivious idiot regardless. Somewhat deconstructed in that in the same episode it is shown that Billy is fully aware of how horrible his life is and it bothers him greatly to the point of acting out in an insane fashion or trying to force others to be happy just so they cannot ruin his happiness anymore.
* RapidFireYes: He would often respond with "yeahyeahyeahyeah..." when he's excited.
* RedOniBlueOni: He's the red oni to Mandy's blue oni. He is impulsive and emotional while Mandy's responsible and stoic.
* ScreamsLikeALittleGirl: His screams sound girly.
* ShesNotMyGirlfriend: Says this word by word when Grim assumed such about him and Mandy in the second episode.
* SimpleMindedWisdom: He makes intelligent observations this more often than he should, making you second guess his stupidity.
* SmarterThanYouLook: Make no mistake Billy is genuinely as stupid as he comes across but he's typically more tuned in to things than he appears.
* StrongFamilyResemblance: He looks a lot like his father and grandfather.
* TokenGoodTeammate: He's the nicest of the trio when compared to Grim and Mandy at least, which admittedly doesn't say much.
* TookALevelInDumbass: By the end of the show, Billy's become an Epic-Level dumbass.
* TooSpicyForYogSogoth: The one and only time Eris attempts to use him as an agent of spreading chaos ends with her having a nervous breakdown. Too put it simply: Billy is too ChaoticStupid for the ''Goddess of Chaos'' to handle.
* UncannyFamilyResemblance: His father, paternal aunt, grandfather, and grandmother all have a GagNose like him (though in Aunt Sis's case it's not pink). In an episode where he gets stuck in prehistoric times and falls in love with a cavegirl, it's shown in the present that ''everyone'' has his nose as a result of being his descendant.
* UnstoppableRage: When he's in this mode, even ''Mandy'' is scared of him. He more or less becomes the most powerful character on the show when in this state, as he always curbstomps his opponent.
* VillainProtagonist: The mildest example of the three, though it must be said that he can be as horrible as Mandy towards Grim and the whole world though in a mindless way. He usually gets a pass due to being mentally stunted and can be harmless when he isn't actively AxCrazy. He's also the only one of the three who ever has heroic motivations, though he tends to do more harm than good when acting on them.
* WhyDidItHaveToBeSnakes: Hates spiders with a passion, which creates some rift between him and Jeff, a spider who sees Billy as his father due to hatching his egg.

->Voiced by: Music/GreyDeLisle

The polar opposite of Billy; a merciless, cynical and manipulative little girl who frequently abuses Grim's power to get what she wants. She almost never smiles and terrifies almost everyone around her, her parents included. Unlike Billy, she's stable, sane and intelligent.
* TheAce: She's hypercompetent at pretty much everything and has almost the entire universe grovelling at her feet. It makes her plans for world domination all the more terrifying due to how ''plausible'' they are.
* ActionGirl: She's the most consistently competent in a fight out of the three of them.
* AllGirlsWantBadBoys: She falls in LoveAtFirstSight with a goth artist boy who Billy befriends in "Crushed". Her reaction is surprisingly adorable. The revelation that he's a poser makes her immediately lose interest in him.
* AmoralAttorney: Her Halloween costume in "Grim or Gregory?" was a lawyer with monster hands for "rending human flesh".
* AnimeHair: Her hair sticks up at the back and curls a little, resembling devil horns.
* AntiHero: She is this at her best moments, and straight up VillainProtagonist at her worst. Despite technically being one of the good guys, it's all about her and follows PragmaticVillainy.
* ArbitrarySkepticism: Despite living in a world where supernatural elements are commonplace, and being friends with the Grim Reaper himself, Mandy adamantly refuses to believe in such things as Santa Claus and the Tooth Fairy.
* BadassNormal: She's capable of scaring the crap out of others just by ''looking'' at them. That's definitely not something an ordinary little girl without any psychical powers can do.
* BewareTheQuietOnes: A stoic kid who is very sadistic.
* BigDamnHeroes: Despite her goal on world domination, she saved the world multiple times. Only because she wants to conquer the world on her own terms.
* BigBad: She's the main antagonist in ''The Grim Adventures Of The Kids Next Door''.
* BigOlEyebrows: Has two large eyebrows.
* BrightIsNotGood: She may be the inverted version of a PerkyGoth. She wears brightly-colored clothes and has a Gothic and morose personality.
* CaptainObvious: She is often treated as a genius for pointing out the obvious because more than half of the time she is surrounded by blundering fools. An example is her reminding Grim to use his scythe to get them out of a tight spot and him enthusiastically calling it a great idea.
* CardCarryingVillain: She makes no excuse for her being evil, and absolutely ''refuses'' not to be seen as anything but a malevolent being.
* TheComicallySerious: She's always overly serious, but is so, in a slapstick and humorous manner.
* CreepyChild: She tricked The Grim Reaper into eternal servitude, using him as her maid and his powers for personal gain, and faces down everything from the Boogeyman to Cthulhu with nothing more than a wry comment. She also never smiles, ever, because doing so would cause the universe to implode. She was also able to take over a large evil brain/alien when it ate her brain.
* DeadpanSnarker: She quite often makes snide remarks about everyone else.
* DeathGlare: She has a constant glare which intimidates anyone.
* TheDreaded: Almost ''everyone'' get scared of her just by using words, and she has already taken over the world because everyone fears her. This goes even to the point where ''Grim'' of all people has nightmares of her.
* EmotionlessGirl: She seems to have only three major emotions: Indifference, disgust, and anger. This trope was exaggerated over time thanks to Flanderization. In season 1, she spoke with more emotion in her voice and was far more prone to looking surprised or worried at the strange things she came across. She also ''smiled'' at the end of the first episode and the universe didn't fall apart.
* EnfantTerrible: Young enough and psychopathic enough to qualify.
* EvenEvilHasStandards:
** She wants to rule the world and [[DystopiaJustifiesTheMeans turn it into a dystopia]], but she is not okay with cheating.
** Quite a few of the disturbing and grotesque things that happen to Billy leave her as speechless and horrified as anyone would. Like him growing a sentient growth in "Billy's Growth Spurt", turning into chocolate and eating himself alive in "Chocolate Sailor", and breaking and twisting his own neck in "Order of the Peanuts".
* EvenEvilHasLovedOnes: She does care about Grim and Billy, and once fell in love with a gothic guy (though she wasn't proud of it). She does seem to have a somewhat normal relationship with her parents (even straining herself to tell her dad she loves him for Father's Day while also giving him Grim's services for the day.) While she also does push them around somewhat, she is shown to be very surprised when her parents admit that they're quite scared of her.
* EvilGenius: She's able to manipulate almost every sentient villain and monster for her own gain, and God help you if you dare try to cross her.
* EvilHero: PlayedStraight. She's one of the main characters and fights against evil, but she herself is far from being a straight hero.
* {{Flanderization}}:
** From simply an apathetic, snarky kid with a HairTriggerTemper and a bossy streak to an [[EmotionlessGirl emotionless]], evil, and totally sadistic psychopath trying to take over the world.
** Her competence was wildly amplified; she went from a smart little girl who could think quick in a pinch to an EvilGenius who not only can pretty much fix or undo anything by just appearing on the scene, but owns everyone apparently.
* FourTemperamentEnsemble: The Choleric. She's task-focused, harsh, and ill-tempered.
* FlatEarthAtheist: She is rendered immune to the Tooth Fairy's powers by revealing, to his face, that she doesn't believe in him.
* FluffyTheTerrible: She's a tiny little girl in black Mary Jane's who almost always have blonde hair shaped like devil horns and wears pink outfits with flowers on them. She's also the scariest being in the universe.
* GaggingOnYourWords: As revealed in "Sickly Sweet," Mandy is such a {{Jerkass}} that even something as simple as saying "please" is nearly impossible for her.
* GeniusBruiser: She is a strong LittleMissBadass who is able to battle monsters with ease, and has a notably superior intelligence, being able to understand complex theories of the world and using her wits and and manipulation skills to get her way.
* {{Goth}}: General consensus is that she's pretty much a Lone Psycho Goth, albeit one that dresses in an ironic fashion.
* GothGirlsKnowMagic: PlayedWith. In contrast to her appearance she has a cynical and dark personality befitting a {{Goth}}, and does not have any inherent skill at magic, but sporadically gains temporary supernatural and magical powers in episodes.
* GreaterScopeVillain: She's never the main villain barring the KND crossover, but she is responsible for enslaving Grim, leading to pretty much all of the supernatural occurrences in Endsville. And while she always stops them, it is explicitly because she plans on conquering the world herself, which she is shown to have done in the BadFuture.
* GuileHeroine: She can take down foes both mortal and immortal in seconds.
* HairDecorations: Wears a black headband.
* HatesBeingTouched: Do not touch her unless you wish to be bitten or punched.
* HiddenDepths:
** The prospect of living a life of quiet desperation is ''the only thing'' that can shake Mandy to her core.
** She seems to actually care for Grim and Billy, as seen in "Big Boogie Adventure" when she was upset when it seemed that Billy may actually have been killed by the Kraken.
* HijackingCthulhu:
** In "Little Rock of Horror", a [[BrainFood brain-eating]] [[EldritchAbomination alien monster]] with a [[Music/{{Voltaire}} familiar singing voice]] has been spending the whole episode being fed by Billy. When Mandy confronts it, it sucks out her brain.... it painfully dies off and its aura immediately changes to resemble Mandy. Her only explanation is that her brain and mind were[[TooSpicyForYogSothoth too "spicy".]]
** Likewise she does this to the "Delightful Reaper" in the KND crossover when she realizes it was too powerful for Kids Next Door's weaponry and ''willingly'' let it assimilate her. Like in the above example, her will takes over the countless others that made up the Delightful Reaper and it takes on her appearance.
* HornedHairdo: Her hairdo is shaped like a pair of horns, making her look fittingly demonic given her demonic personality.
* HumiliationConga: The episode "Zip Your Fly!" is a big instant of suffering a series of undignified predicaments for Mandy. After she uses Grim's magical zipper to take her head off, a fly gets in the way when she zips it back. She switches heads with it, having to move with a comically small body. She then gets stuck in fly paper and Harold attempts to flush her down the toilet. She lost half the zipper in garbage and ended up eating an entire junk yard to find it.
* HypocriticalHeartwarming: She would never let Billy do any of the things that she does.
* ImprobableWeaponUser: In the Creator/CartoonNetwork game "The Fight Before Christmas", she uses a toy hammer, a toy plane, a doll[[note]]which she hurls like a throwing star[[/note]], a fistful of marbles and a pan of popcorn as weapons against the evil toys overrunning Santa's workshop.
* InformedDeformity: In ''My Fair Mandy,'' a skilled make-over artist was shocked by her appearance, at first mistaking her for an angry tree stump.
* IronicName: Her name means "adorable" or "lovable", despite her bitter and cynical attitude.
* IronLady: Her ultimate goal in life is "[....] [[DesperatelyLookingForAPurposeInLife to do something]] [[YoungConqueror important]]!" She eventually is elected president of the United States, and in the distant future, will rule the world.
* {{Jerkass}}: Develops more and more into being a heartless and unsympathetic jerk after every season. Her beast transformation in "Sickly Sweet" even makes her sound like a ''literal'' ass (the animal). Hell, that episode shows that even trying to do anything nice is nearly impossible for Mandy, to the point where she has physical difficulty just trying to say "Please."
* JerkWithAHeartOfJerk: While she does do heroic actions like saving Billy from himself or whatever MonsterOfTheWeek they're up against, as well as saving the whole planet, Mandy will ''always'' have a selfish motive in mind no matter what -- but...
* JerkWithAHeartOfGold: ...she is also shown to care about Grim and Billy, having small and rare moments where she's shown to be worried about their well-being. Another proof is that the real reason why she doesn't smile, is because the world would end if she did so.
* KarmaHoudini: RuleOfFunny usually dictates that she gets off scot-free -- [[KarmaHoudiniWarranty but there are a few occasions where she's outwitted and beaten]].
* KickTheDog: She can be incredibly cruel, especially to Grim, Billy, and Irwin.
** As if taking Gregory's Halloween candy in "Grim or Gregory?" wasn't enough, she also admits not to care that she made the kid cry when Billy admonishes her for it.
** Another rather cruel moment from Mandy occurs in "The Greatest Love Story Ever Told Ever", where she reveals to Irwin and Nergal Jr. that [[TheChessmaster she knew they would fight over her and ruin the Valentine's Day school dance and that this was exactly what she wanted to happen]], rationalizing that [[EvilIsPetty if she can't enjoy Valentine's Day, no one else should]].
** Stealing the Golden Nose of Chipotle for her own ends and leaving Grim, Billy, and Harold behind in Mexico in "El Dia de Los Muertos Estupidos".
* KickTheSonOfABitch: Whenever she torments [[AlphaBitch Mindy]] or [[BarbaricBully Sperg]], the harshness of her actions is usually offset by how rude they were being.
* LackOfEmpathy: Whatever empathy she has is locked away in the cold dark recesses of her soul.
* LittleMissBadass: Wears pink, is blonde, snarks almost constantly, and makes the Grim Reaper her personal bitch in the first episode.
* LittleMissSnarker: This line pretty much exemplifies it:
-->''"Power tools in the dark? Darwin should be paying you two goons royalties."''
* MaddenIntoMisanthropy: It's implied that two things helped complete Mandy's metamorphosis into the cynical tyrant we all know and love: Mindy's inane, meaningless prattle, and having to deal with the perpetually moronic Billy every single day of her life.
* ManipulativeBitch: She manipulated the Grim Reaper, Eris, Hoss, and sometimes even Irwin to do her bidding.
* NobleDemon: She's TheDreaded, brooding, anti-social and occasionally evil but she's also loyal and stays close to her friends, always keeps her word and never cheats.
* TheNoseless: She has no nose, but she does have nostrils.
* NotSoStoic: Some things ''can'' get under her skin, if rarely. Even she wasn't immune to being called ugly or unattractive.
* OddFriendship: She willingly hangs out with Billy, despite the two of them being polar opposites.
* OffModel: She looks decidedly... wrong in ''Underfist''.
* OneWingedAngel: Her future self from the episode "Mandy the Merciless", where she is a giant worm.
* OnlySaneWoman: Trades roles with Grim as the most reasonable and rational of the group, depending on the episode.
* PerkyGoth: Completely {{Inverted}}; she dresses like a standard little girl, but embodies the Lone Psycho Goth stereotype.
* PerpetualFrowner: It's mentioned on more than one occasion that she ''never'' smiles; in fact, it's revealed in "My Fair Mandy" that if she ''does'' smile, it will cause a RealityBreakingParadox.
* PetTheDog:
** She will occasionally meditate on the possibility that she actually cares about Grim and Billy...[[IgnoredEpiphany but ultimately dismiss the errant thought.]]
** In "Halls of Time", she seems legitimately horrified at the idea of Irwin being erased from existence.
** Accepting Saliva (in her own way).
* PinkGirlBlueBoy: The pink girl to Billy's blue boy. She wears a pink dress, while Billy wears blue jeans and a shirt with a blue stripe.
* PinkMeansFeminine: Averted. Mandy usually wears a pink dress, but she isn't that feminine.
* PragmaticVillainy: Oh she'll help save the world alright, but only because she needs it in pristine condition for when ''she'' conquers it herself. In the same vein, she'll always help defeat the MonsterOfTheWeek, but only because the world is ''hers'' and she won't let anyone else take it from her.
* PsychoticSmirk: By way of EarlyInstallmentWeirdness, but before it became a major defining trait of hers that she never smiles, she had a couple evil grins in response to Grim's suffering in "Meet the Reaper" and "Look Alive!".
* RaisedByWolves: Played for laughs. Her parents claim that wolves ''came'' to raise her as her own when she was born.
* RedOniBlueOni: She's the blue oni to Billy's red oni. She is stoic and responsible while Billy is impulsive and emotional.
* SlapstickKnowsNoGender: Though rarer than with Billy, she's not immune to physical comedy. Whether that's being [[AshFace burned to a crisp]] by Cerberus in "Mandy Bites Dog", or being [[CoveredInGunge covered in snot]] twice after Grim sneezes on her in "Night of the Living Grim".
* SociopathicHero: She enjoys people's pain and is one of the main protagonists.
* TheSpock: Intelligent and deadpan.
* TheStoic: She never smiles fully at all. It's for the best.
* SugarAndIcePersonality: She is actually shown to be somewhat caring and even passionate in some episodes despite usually coming off as cold and uncaring.
* SurroundedByIdiots: As seen in CaptainObvious above, she seems the only person with a brain most of the time.
* TinyTyrannicalGirl: She's a little girl who doesn't take guff from anyone. In fact, almost everyone in the show is afraid of her.
* TokenEvilTeammate: The only hero who's more evil than a demon from the underworld.
* TomboyWithAGirlyStreak: For someone so decidedly unfeminine, she has a tendency towards pink and girly things. While there's an underlying hint of irony to it, she seems to legitimately like them.
* TookALevelInJerkass: Mandy became more hostile and disrespectful towards her friends in later seasons.
* UnsympatheticComedyProtagonist: She has no positive qualities beyond being intelligent and competent, both of which she uses to make the world a bad place.
* VillainsOutShopping: Whenever she isn't scheming, she's just spending time, with Grim and Billy at their house.
* VillainProtagonist: She's one of the main characters and is so evil that she makes the personification of death look like a nice guy in comparison.
* WhenSheSmiles...she tears the very fabric of time, space, and reality apart. For the sake of humanity, it's better that she doesn't smile. Although in some earlier episodes, this trope is played straight.
* WhyDidItHaveToBeSnakes: In "Attack of the Clowns", both Billy and Grim claim that she's afraid of ''professional figure skaters,'' though she denies this, only saying she merely distrusts how they skate.
* WiseBeyondHerYears: She may be a real bitch but she's EASILY the smartest character on the show.
* YouGoGirl:
** Billy wouldn't allow Mandy in his baseball team because she's a girl. Trying to teach him a lesson, she disguised herself as a boy named "Manfred" by donning a baseball cap.
** Billy and Irwin made a racing team and wouldn't allow Mandy in because she's a girl so she started her own team with Grim, who was rejected from Billy and Irwin's for being a skeleton. [[SubvertedTrope Pud'n won]].


->Voiced by: Creator/VanessaMarshall

A nerdy boy and a close friend of Billy's. He has a crush on Mandy. Later revealed to have monstrous heritage and becomes a crucial member of Underfist.
* AbhorrentAdmirer: Mandy can't stand his crush on her. All of the occasions of her reciprocating his feelings were either due to magical influence or [[DudeShesLikeInAComa being unconscious]].
* AccidentalHero: Him unintentionally suffering all of Mandy's pranks that were meant for Jack in the Halloween special is what ultimately leads to Jack being defeated.
* {{Adorkable}}: He's a nerdy boy who desperately tries to look cool and he also comes off as sympathetic due to his relentless suffering.
* BlackAndNerdy: Though he's not that smart, he's black and has geeky interests and pastimes.
* BlackBestFriend: He's black and Billy's closest friend aside from Mandy.
* BreakoutCharacter: Gets steadily more appearances until becoming the main character of ''Underfist''.
* ButtMonkey: Gets a lot of punishment along with Billy.
* CharacterizationMarchesOn: Early episodes simply portray him as Billy's nerdy SatelliteCharacter best male friend, without a trace of the JiveTurkey StalkerWithACrush traits that would come to define him.
* TheChewToy: He is pretty much the [[WesternAnimation/SouthPark Kenny]] variant of this show, as some episodes ended with him getting killed, yet he still comes back for more abuse.
* DarkIsNotEvil: He's a mish-mash of various monsters, but is almost always a harmless and obnoxious nerd.
* {{Dhampyr}}: At least, he is 1/4 Vampire (his paternal grandpa is Dracula).
* DoggedNiceGuy: To Mandy. She ''never'' reciprocates his affections, no matter what he does.
* EyeGlasses: His glasses will sometimes contort to his expression. His eyebrows will also overlap his glasses sometimes.
* FourTemperamentEnsemble: The Phlegmatic. He's a nice guy for the most part and doesn't usually seem to be aware of Mandy's faults.
* HalfHumanHybrid: 1/2 Mummy, 1/4 Vampire, and [[GeniusBonus 22/7]] nerd.
* JerkassBall: Some episodes have him become really mean when the plot calls for it.
* JiveTurkey: Later episodes have him pepper his sentences heavily with black slang, most notably "yo". This is PlayedForLaughs, as it is incongruous with his otherwise nerdy appearance and behavior.
* MadLove: Keeps a huge crush on Mandy, no matter how many times she rejects him.
* OurVampiresAreDifferent: He's Dracula's grandson and aside from the traditional vampire powers has also demonstrated being able to fire energy blasts.
* RedEyesTakeWarning: [[spoiler:His eyes glow red near the end in ''Underfist''. And that's when [[BigBad Bun-Bun]] realized he was [[OhCrap screwed]].]]
* SixthRanger: The most frequent character to join the main trio on their adventures, though he has a tendency of dying or otherwise being incapacitated early on in them, before anything really gets a chance to happen.
* StalkerShrine: In "Billy and Mandy's Jacked-Up Halloween", it is shown that he has a shrine where hundreds of Mandy's eyes glare at him. It is one of the most disturbing things in the special.
* StalkerWithACrush: To Mandy. He's hopelessly in love with her and doesn't let anything stop him from following her around and trying to get close to her.
* StrawLoser: He makes Billy seem cool in comparison. Even after we learn about all of his monster heritage, he still comes off as a useless loser (until ''Underfist'' anyway).
* SuperPowerLottery: Irwin's being a HalfHumanHybrid has given him several powers in ''Underfist'' such as: {{Flight}}, HandBlast (called Mummy's Curse), MummyWrap, SuperStrength and VoluntaryShapeshifting.
* TheyKilledKennyAgain: Has a fairly high tendency of dying whenever he appears, but always comes back. It might have to do with his mummy/vampire heritage.
* TookALevelInBadass: In ''Underfist'', he becomes more competent and is no longer a ButtMonkey.
* UsedToBeASweetChild: Inverted, believe it or not. In "Heartburn", Billy and Mandy play around with Grim's camera that shows the true self of the person on the film. Irwin's heart reveals to be half good like Billy's and half evil like Mandy's, and when questioned, he admits he was an EnfantTerrible at birth before his dad [[HeelFaceTurn turned him around]].
* VerbalTic: ...yo. Seems inherited; as his dad calls people "dude", and his grandmama calls her loved ones "baby".
* VocalEvolution: In his earliest appearances, Irwin's voice was stuffier and he had a slight lisp. Eventually, his voice became a bit more clear, but still kept a unique sound.
* WithFriendsLikeThese: He's a pretty unreliable friend to Billy, to the point where he almost seems to hang out with him exclusively to be around Mandy. Billy's not that great of a friend to him either; he once stopped Sperg from giving Irwin a wedgie... So that ''Billy'' could do it for him.
* {{Yandere}}: When he got the scythe in "Scythe for Sale", his first thought was to use it to brainwash Mandy and go on a forced date.

->Voiced by: Creator/RichardStevenHorvitz

Billy's father and Gladys' husband.
* AbusiveParents: Surprisingly, depending on the episode, he qualifies as this much more than his wife. Because of his lack of any maturity or intelligence, he's often incapable of behaving anywhere close to a proper parent and is more like his equal mentally. He is capable of childishly mocking his son, for playing with the dinosaur toys in ''Toys will be Toys'' and is even dense enough, to bully his son and ask for his lunch money in ''The crass Unicorn''.
* {{Autocannibalism}}: In "Super Zero", while picking his nose, he pulled his own brain out through his nose and proceeded to eat it.
* BumblingDad: Like his son, he often doesn't care about anything and has a small IQ.
* CloserToEarth: While he is dumber than Gladys, he is not as prone to fits of nervousness like she is and is quite relaxed around Grim.
* CrouchingMoronHiddenBadass: A former Navy SEAL, according to "Dream Mutt".
* TheDitz: Billy got more than just his looks. This applies even before he TookALevelInDumbass considering he didn't seem to notice that Grim was actually the Grim Reaper!
* FatIdiot: He's obese and while not a stupid as his son, he's close.
* {{Flanderization}}: He actually didn't seem that stupid early on, just lazy and apathetic to the fact that his son was friends with the Grim Reaper. By later episodes, he's almost as dumb as Billy.
* HappilyMarried: He and Gladys are clearly happy together.
* HiddenDepths: In his youth, he was apparently smart enough to get accepted into Harvard University. [[spoiler: Too bad his acceptance letters were stolen by a sentient tree]] He was also a Navy SEAL at some point, as well as a world-class ballet dancer.
* MrViceGuy: He's overall a decent guy, even if he's disgusting and rather stupid.
* NeverLearnedToRead: Admits to being illiterate in "Billy Idiot".
* NoodleIncident: It is shown in "Here Thar Be Dwarves" that he once [[spoiler:dressed up like Sasquatch, kidnapped Billy and did something to him that left him with "emotional scars"]]. This might explain why [[spoiler:his wife thinks she's had an affair with Sasquatch]] too.
* OnlySaneMan: In the early episodes, before the above mentioned Flanderization, he was this compared to his wife and son.
* RedOniBlueOni: He's the blue oni (more reasonable and grounded) to Gladys' red (prone to irrational fits).
* StrongFamilyResemblance: He's an older, fatter Billy with a pompadour. A flashback in "Billy Idiot" shows that he also bears a resemblance to his own father.
* TookALevelInDumbass: Starts out as seeming reasonably intelligent, but eventually becomes much dumber.
* UglyGuyHotWife: His wife is considered quite attractive by some while he looks almost exactly like an older, fatter version of Billy.

->Voiced by: Creator/JenniferHale

Billy's mother and Harold's wife.
* AmbiguousDisorder: She's implied to be the source of Billy's psychopathic outbursts.
-->'''Harold:''' Did someone forget to take their medicine today?
* AngerBornOfWorry: Her angry side was born from her worry of Grim, and she learned to not fear him, but destroy him.
* DotingParent: She is a caring but overprotective mother to Billy.
* FieryRedhead: She has red hair and when angered can even make Grim run away in terror.
* HappilyMarried: She and Harold are happy together.
* MamaBear: Mostly in the earlier seasons. If she considers you a danger to Billy, she will do everything in her power to make sure you stay ''as far away from him as possible''. It's one of the main reasons why she hates Grim so much, and wants him out of her house.
--> '''Gladys:''' ''(after beating Grim over the head with a mop)'' STAY AWAY FROM MY BABY!!! He's allergic to the undead!
* NoodleIncident: Apparently, Gladys has had some sort of...[[GettingCrapPastTheRadar less than wholesome liaison]] with [[InterspeciesRomance Sasquatch]], which is referenced in "Bearded Billy", wherein Billy grows a whole lot of hair and Gladys mistakes him for Sasquatch. [[spoiler:Though given that "Here Thar Be Dwarves" had a flashback of her husband dressing as Sasquatch and kidnapping their son while on a picnic, it's possible that it was actually Harold in disguise]].
-->'''Gladys:''' (''attacking Billy thinking he's Sasquatch'') I TOLD YOU IT IS ''OVER'' BETWEEN US!
* ProperlyParanoid: With all the dangerous things that happen when they're together, it's no wonder she worries about her son being with Grim.
* RedOniBlueOni: The red oni to Harold's blue oni. She's often more emotional and hot-blooded than her husband.
* SelfServingMemory: She remembers the circumstances that led her to leave a ''little'' differently than they actually happened.[[note]] Grim's presence did drive her to a mental breakdown but that was largely due to ContrivedCoincidence making it look like she was losing her mind and deciding to leave for the sake of her own sanity while upon her return she makes it out that Grim was deliberately tormenting her and chased her out rather than leaving voluntarily [[/note]]
* StepfordSmiler: Type 3. She tries to maintain a sense of normalcy and care for her family, but is always close to going over the edge because of Billy's antics. That smile ends up being frozen and forced much of the time as a result.
* SuperOCD: She goes nuts when things are out of order or untidy.
* TwitchyEye: Her eye twitches whenever something goes wrong or the supernatural happens.
* UglyGuyHotWife: She is considered quite attractive by some, while Billy's dad, Harold, looks almost exactly like an older, fatter version of Billy.
* WomenAreWiser: Subverted. While smarter than her husband, she's also mentally unstable and prone to fits of homicidal rage (which she passed to her son.)

[[folder:Mandy's Parents]]
->Voiced by: Creator/DeeBradleyBaker (Phillip), Creator/VanessaMarshall (Claire)

Mandy's parents. They are terrified of her.
* ADayInTheLimelight: "Scary Poppins" explores their relationship with Mandy.
* GoodParents: For the most part. They love and take care of Mandy despite the horrible treatment they receive.
* HippieParents: They seem to be {{Beatnik}}s hence why they're so okay with Mandy's abuse.
* OutOfFocus: They're utilized considerably less than Billy's parents. In a deleted scene, they explain they're rarely in episodes because they're afraid of Mandy.
* PushoverParents: They cave into Mandy's desires. Part of the reason is because they fear her, but it's implied she has some kind of supernatural control over them.
* UglyGuyHotWife: Not as extreme as Harold and Gladys. Phillip would be average looking guy if it wasn't for his big nose, while Claire is attractive.


[[folder:Hoss Delgado]]
->Voiced by: Creator/DiedrichBader

A spectral exterminator who frequently encounters Grim, Billy and Mandy in his various exploits, and briefly dates Eris, Goddess of Chaos. Later becomes part of the Underfist team, albeit reluctantly at first.
* AccidentalMisnaming: In ''Underfist'', he keeps getting Irwin's name wrong. He calls him "Irving", "[[ShoutOut Ur]][[Series/FamilyMatters kel]]", and "Ivan". [[spoiler:He correctly calls him "Irwin" while saving him from the giant pumpkin-headed candy monster.]]
* ArtEvolution: He's noticeably older looking in ''Underfist'', sporting a beer gut and streaks of grey in his hair. He's also even larger than before and has a chainsaw leg.
* AntiHero: He believes that all monsters are a threat, which causes him to murder any monster he ever sees, even innocent and harmless ones.
* AwesomeMcCoolname: His name is a pretty good indicator of his outrageous badassery.
* BasementDweller: ''Underfist'' has him still living with his mother.
* BigBrotherMentor: Acts as a rather half-assed mentor and big brother figure to Billy in a few episodes, and Irwin in others.
* BunnyEarsLawyer: He's a tad eccentric and not very bright, but he is a ''damn'' good spectral exterminator.
* ButtMonkey: ''Underfist'' has him suffer several painful injuries as well as moments of humiliation.
* CharacterizationMarchesOn: He's presented as a bit of an incompetent buffoon in his first appearance. In all of his following ones he is shown to be extremely competent at his job, with most of his humor being derived instead from his excessive and ridiculous monologues.
* TheComicallySerious: His lines are almost always ridiculous, but delivered in a completely serious BadassBaritone.
-->''"I've been bitten by ghosts, haunted by mome raths and slapped by vampires... '''I think I've earned a free hotdog.'''"''
--> ''"Are you stepping in my cornflakes? I'll tell you something about stepping on someone's cornflakes... '''it's a weird way to eat cornflakes'''"''
* DatingCatwoman: His relationship with Eris, given that he hunts supernatural creatures and she is the Goddess of Chaos.
* DarkAndTroubledPast: Parodied. He has an exceedingly long and convoluted one that is also ridiculously lame, involving wetting the bed till he was 35, being raised as a girl for most of his childhood, poking his eye out after running with scissors and getting constantly one upped by ''a traffic cone''.
* {{Deuteragonist}}: While Irwin is the main character of ''Underfist'', Hoss is the official leader of the team, and his relationship with Irwin is one of the most central parts of the plot.
* DumbMuscle: He's far from the brightest bulb, but is an excellent fighter.
* DubNameChange: From Hoss Delgado to Rene Gado in the Latin American dub, a PunnyName of Renegado (renegade).
* EmpoweredBadassNormal: He replaced his own hand with an Iron fist that can turn to all sorts of weapons from a gun to a ''chainsaw''. He also replaced his leg with a chainsaw in ''Underfist''.
* EyepatchOfPower: He wears an eyepatch.
* {{Expy}}: He's based on [[Film/EscapeFromNewYork Snake Plissken]] and [[Franchise/EvilDead Ash]].
* FreudianExcuse: In ''Underfist'', he eventually confesses to Irwin that his intense hatred of monsters comes from being scared by a monster in his closet when he was a kid. [[spoiler:Said monster was actually Bun Bun in a witch costume]].
* GoKartingWithBowser: Despite his hatred of Grim, he's perfectly willing to pal around with him when the situation calls for it.
* GoodIsNotNice: He is seemingly the only person in the world who fights supernatural threats besides the main trio, who are more often than not the cause of them, but mercilessly hunts even harmless ones like Jeff and Fred and tends to act like an indifferent jerk to other people. This changes after Irwin saves his life in ''Underfist'', making Hoss realize that there are some good monsters after all.
* GutturalGrowler: Speaks in a low growl.
* {{Hammerspace}}: Where he keeps all the random attachments for his hand (his chainsaw, goo cannon, crossbow that fires a ''chainsaw'').
* HeroAntagonist: It varies. His hatred of Grim puts him at odds with the trio on occasion, but he can be an ally just as frequently, if not more.
* HiddenDepths: Despite being a powerful tough guy, one of his favorite things is Pat the Baker, a simplistic baking video game that is also Billy's favorite game. According to him, he never leaves home without it and he and Billy bond over playing it at the end of an episode.
* {{Hunk}}: According to Eris. He's so obscenely muscular and hairy that he can be easily mistaken for bigfoot when shirtless.
* LanternJawOfJustice: Has a perfectly square jaw and is all about defeating supernatural threats.
* {{Narcissist}}: He's pretty self-absorbed, to the point where his debut has him trying to justify a reason for a random street vendor to give him a free hot dog.
* OneManArmy: Generally has an easy time taking out hordes of supernatural monsters, though he has quite a bit more trouble dealing with Eris.
* PermaStubble: Pretty much a given that he'd always have a five-o'clock shadow, considering who he's based on.
* PreAssKickingOneLiner: When he isn't belting out complicated and bizarre metaphors that don't apply to the situation, he's delivering really campy one liners.
* RatedMForManly: An over-the-top parody of this. Everything he does exudes hyper-masculinity, even the most mundane, nonsensical or pathetic tasks.
* {{Retcon}}: ''Underfist'' presents him as having fallen into depression following his breakup with Eris, gaining a beer gut, moving in with his mom and generally being a much more pathetic mess than in the past. This goes against his multiple appearances after the breakup in the original series, where he was no different from how he normally was, as well as the fact that ''he'' was the one who initiated the breakup, not Eris.
* SourSupporter: Did ''not'' want to be part of Underfist, but President Mandy ordered him; by the end, he's warmed up to the idea.
* SwissArmyAppendage: His cyborg hand (it was outright called his "Swiss Army Hand" in his video game profile). It can transform into a variety of things, ranging from a chainsaw-firing crossbow to a nose-shaped detector to a bouquet of flowers.
* TankGoodness: His giant fist-and-arm shaped tank which provides Fred Fredburger the idea for the Underfist team. It later gains a blue-and-yellow paint job, but got wrecked by one of Bun-Bun's rotten gems.
* TheStoic: Most of the time, he's serious and unemotional.
* TragicHero: His gruesome experiences with monsters has caused him to attempt to destroy every monster he sees, even harmless ones. This often gets him to become a HeroAntagonist.
* TookALevelInBadass: In the past. He used to be a loser like Irwin, until he became the Hoss we know. Within the show itself, he's portrayed as being incompetent in his first episode and hypercompetent in all of his following ones.
* TookALevelInDumbass: He was never particularly smart, but ''Underfist'' takes his lack of intelligence a step further.
* TopHeavyGuy: His upper body becomes bigger and bigger while his legs become tinier. By ''Underfist'' he's obscenely beefy and supported by two tiny tooth pick legs.
* VanHelsingHateCrimes: He's a spectral exterminator, hunting monsters for a living. The problem being that not all of them are ''bad''; [[DontFearTheReaper Grim]], for instance. He even took out a bunch of ''lawyers'' because [[EvilLawyerJoke he said they weren't human]]. Even after he retired from his profession, he still holds some prejudices towards monsters. In ''Underfist'', he refuses to let Jeff and Fred Fredburger come with him to the Underworld because he doesn't work with monsters (or "[[HypocriticalHumor one-eyed weirdos]]", in Skarr's case). He also hesitates in joining Underfist because of this. [[spoiler:There's also his fights with Irwin, and the fact he tried to ''kill'' Irwin once he found out he was a vampire ''and'' a mummy.]]
--> '''Hoss:''' [[spoiler:[[AccidentalMisnaming Ivan]] is a [[HybridMonster mummy-vampire]]? That means you lied to me ''twice'' when you said you weren't a monster!]]
* TheWorfEffect: Very present throughout ''Underfist'', where he keeps getting his ass kicked in spite of all the previous times he's proved to be able to hold his own against any manner of supernatural creature.

[[folder:General Skarr]]

->Voiced by: Armin Shimerman

[[WesternAnimation/EvilConCarne Hector Con Carne's ex-paramilitary commander]]. He moved to Endsville after Con Carne's organization shut down, and became Billy's neighbor (much to his distress) and an avid gardener. Later joins the Underfist team.
* AntiHero: In "Underfist", he is the Unscrupulous Hero. He does join the others in forming the titular team, but is still not completely a good guy.
* BadassBeard: In "Underfist", he has a goatee.
* BaldOfEvil: As a parody of a paramilitary general, he has no hair on his head. And he doesn't mind it, he cared more about his bald chest.
* BerserkButton: In the name of all that is good, do ''not'' mess with his garden.
* BornUnlucky: Even ignoring his wimpiness and stupidity he tends to have such terrible luck that he can never establish himself as a genuine threat.
* ButtMonkey: He suffers too many misfortunes to take seriously, yet he's too mean to really pity.
* DubNameChange: He is named General Ernecio in the Latin American dub.
* FakeDefector: Pretends to betray the other heroes and side with Bun-Bun in ''Underfist''.
* GoodHairEvilHair: Gains a handlebar moustache and a goatee in ''Underfist''.
* MeaningfulName: He has a scar on one of his eyes.
* TheNeidermeyer[=/=]TheStarscream: Was an unstable and disloyal subordinate back when he worked for Hector Con Carne. He [[ExploitedTrope exploited the trope]] in ''Underfist''.
* RealMenWearPink: Is often seen gardening his front yard happily.
* ScarsAreForever: Skarr will be around fitting right into his name forever.
* SissyVillain: A megalomaniac who knows his way around an attractive garden.
* {{Transplant}}: The only ''Evil Con Carne'' character to get elevated to recurring status here.


->Voiced by: Creator/RachaelMacFarlane

An obnoxious and snobby girl from Billy and Mandy's school that is obsessed with proving her worth to Mandy, who doesn't care for her.
* {{Adorkable}}: Surprisingly showed some traits of this in "Wrath of the Spider-Queen" and "Underfist", like acting giddy after defeating spiders with her bare hands or randomly breaking out into an air guitar solo of a song she just sang.
* AlphaBitch: A much younger AlphaBitch, as well as an incredibly obsessive one. For example, she loses her head cheerleader position to Mandy (who just shouts the game plans to the team) and, after consulting the "patron saint of cheerleading" (a trophy she thinks is talking), decides the best solution is to incapacitate her in some way in the middle of a match, or, failing that, blow her up. If she sees Mandy with anyone aside from Billy or Irwin or the like, she walks up to them, puts on an obscenely perky face, and says "You're my best friend!"
* AssholeVictim: Thankfully, she's also one of the show's regular victims of whatever supernatural power is at hand in the episode.
* BrattyHalfPint: She's definitely a rude and insufferable kid.
* DisproportionateRetribution: When Mindy first moved in Endsville, Mandy actually tried being nice to her because she looked alone. She quickly regretted it hearing her chatterbox antics and told her to shut up. Mindy didn't take it well, and had became her obnoxious rival ever since.
* EvilRedhead: She has ginger colored hair and is a nasty, downright obnoxious AlphaBitch.
* {{Foil}}: To her rival Mandy. They have similar names and both of them are mean and rude, but otherwise they are complete opposites: Mindy is a GenkiGirl in contrast to Mandy's EmotionlessGirl; Mindy is shallow, spoiled, and stupid while Mandy is dark, cynical, and intelligent.
* GenkiGirl: A rare evil variant of a girl who's hyper.
* HeelFaceTurn: At the end of "Underfist", she turns against Bun Bun and decides to stop being evil.
* {{Jerkass}}: She constantly torments Mandy in a verbal manner (In fact, her catchphrase is "LOSER!") and taking it all in stride.
* LickedByTheDog: A subversion in one episode in which this literally happens and she responds by acting even ''worse'' than usual!
* PopularIsDumb: Demonstrated in "Wishbones".
-->'''Mindy''': But as beautiful and popular as I am, I bet there are some people who've never even heard of me: [[ArtisticLicenseGeography people in countries like Paris or Toronto, or in cities like Africa]].
* RichBitch: She is the evil, rich and spoiled queen bee of the school.
* TheRival: She is frequently a rival to Mandy
* SchoolUniformsAreTheNewBlack: Is almost always seen in her school clothes even before the school adopted uniforms even in the later seasons.
* SmartBall: Her intelligence fluctuates from being almost as cunning and manipulative as Mandy to being a complete airhead.
* TookALevelInBadass: Twice in a row she's become more competent and dangerous; in both "Wrath of the Spider Queen" and "Underfist".
* TookALevelInKindness: At the end of both "Wrath of the Spider Queen" and "Underfist".
* VillainSong: She sings "Trick-or-Treater Eaters" in "Underfist" while whipping up a brew to make the candy monsters stronger.
* WeUsedToBeFriends: Was best friends with Mandy in kindergarten, until Mandy got sick of how much she talked and stopped hanging out with her.


->Voiced by: Jane Carr

A classmate of Billy and Mandy's, Pud'n is a very sensitive young boy who is constantly picked on by Sperg.
* BewareTheNiceOnes: He got into an epic struggle with a demon rabbit and causes an explosion by squirting the custard out of two éclairs, and he once viciously beat up General Skarr when he thought Skarr was responsible for turning all his neighborhood rabbit friends into monsters.
* ButtMonkey: It's very common for him to get hurt or humiliated.
* BrownBagMask: He wears one while competing in a go-kart race with the other kids. He miraculously wins, despite his go-kart being nothing more than a simple red wagon. Mandy ends up unmasking him, and he starts crying like a baby when he sees everyone cheering for him.
* DubNameChange: His name is changed to Pecas in the Latin American dub.
* InTouchWithHisFeminineSide: He's weak, seems completely non-aggressive, loves fluffy pink bunnies, and cries at the drop of a hat.
* KiddieKid: The most stereotypically childish of the child characters. He likes cute things and often cries like a baby when things go bad for him.
* RaisedByWolves: In one episode, Billy asks what Pud'n is doing outside so late at night, only for Pud'n to show that he was raised by wolves, and they live outside. The wolves are watching television and one politely waves at Billy, telling him good evening.


->Voiced by: Greg Eagles

The local bully, who constantly bullies Billy, Irwin, Pud'n, and other kids to no end.
* BerserkButton: Don't talk bad about his mom, especially if it causes her to cry right in front of him.
* TheBully: He is often seen tormenting Billy, Irwin, or other kids.
* DubNameChange: He is called Valente in the Latin American dub.
* EvenBadMenLoveTheirMamas: He's very defensive of his mother.
* HeroicSacrifice: [[spoiler: Saves the world from alien invaders by using the explosive chip in his head. [[MadeOfIron He manages to bully people without a head]]]].
* {{Jerkass}}: He's very mean to most kids, but primarily to Billy, Irwin and Pud'n.
* JerkWithAHeartOfGold: In "Billy and Mandy Moon the Moon", he gets a bomb planted in his skull that explodes in a day's time...all while Billy whomps the other aliens mercilessly. What does Sperg do? Make his way to the control room, where he eventually detonates, blasting the alien ship out of the sky.
* RealMenWearPink: He loved to sing showtunes. In "Tricycle of Terror," he expresses a desire to be on Broadway.

[[folder:Aunt Sis]]

->Voiced by: Music/GreyDeLisle

Harold's sister and Billy's Aunt, who later marries and starts a family with Nergal at the center of the Earth.
* AscendedExtra: She first appeared at the end of the episode with Grim's first encounter with Gladys, taking her away from home, only to later had her own focus episode and later marrying Nergal.
* TheCameo: She is briefly seen on a picnic with her husband and son in ''Underfist''.
* EveryoneCallsHimBarkeep: Her real name is never given. She's named by her relation to Billy's family. She's Billy's aunt and Harold's sister.
* GagNose: Her nose is as big as Billy's and Harold's noses.
* HappilyMarried: She ends up marrying Nergal and having a son with him.
* MaidenAunt: Before marrying Nergal. Gladys explicitly calls her a spinster when explaining to a curious Billy as to why she "ain't got nobody". PlayedForLaughs in that she met her true love during a dance contest, and he left her once the contest was over. Gladys explains this was the "Greatest four and a half minutes of her life"


->Voiced by: Creator/PhilLaMarr

Irwin's dad and Tanya's son. He's friends with Harold, and it's revealed he's Dracula's son as well.
* BlackAndNerdy: Like his son, he's a black geek.
* BlackBestFriend: He is black and Harold's best friend, [[GenerationXerox much like the relationship between their own sons]].
* BoyMeetsGhoul: He married and had a child with an undead mummy.
* {{Dhampyr}}: As Dracula is his father, he's half-vampire.
* HotGuyUglyWife: Dick is an average-looking guy, while his wife is a hideous mummified corpse.
* TranslatorBuddy: He interprets what his wife says in "King Tooten Pooten".
* VerbalTic: Tends to end his sentences with "Dude!".



->Voiced by: Creator/PhilLaMarr

Irwin's grandmother, more commonly known as "Grandmama."
* AmazinglyEmbarrassingParents: The short "Hate in an Elevator" had her become an amazingly embarrassing ''grand''parent by telling humiliating stories about her grandson to Mandy while the three of them were stuck in an elevator. Once they're free, she continues to embarrass her grandson by telling the stories to the news crew that interviews them about their time stuck in the elevator.
* CoolOldLady: Unlike many of the adults on the show, she's more competent. You qualify as this if you're able to get [[spoiler: Dracula, your husband]] to shut up and just eat their dinner.
* CurbstompBattle: Delivered a one-sided beating to Principal Goodbling.
* FourthDateMarriage: With [[spoiler: Dracula]]. A few steps less than fourth date actually. More like getting married after having just met.
* IWasQuiteTheLooker: She was much prettier and attractive in her younger years.
* ThirdPersonPerson: She occasionally addresses herself as "Grandmama".

[[folder: Ms. Butterbean]]

->Voiced by: Renee Raudman

The teacher of Billy and Mandy's class in Endsville Elementary. She is very apathetic towards teaching, only doing her job for a paycheck and is often seen sleeping in class.
* AndNowYouMustMarryMe: She gets kidnappped by Fred Flintstone in "Modern Primitves", which causes her to demand that he marry her and give her 2.5 kids.
* ApatheticTeacher: Doesn't give a lick about her job.
* AssholeVictim: in "Substitute Teacher" she lets Sperg bully Nergal Junior. Nobody feels sorry for her when Junior kidnaps her and ties her to the ceiling
* FourEyesZeroSoul: She wears a pair of glasses and is a selfish, callous person.
* HotTeacher: She's a young, attractive woman. That's just about the only positive quality she has.
* {{Jerkass}}: A callous woman who is openly mean and indifferent to her students.

[[folder: Principal Goodvibes]]

->Voiced by: Creator/ChrisCox

The principal of Endsville Elementary and kind of a wuss.
* ButtMonkey: Yet another character on the show who tends to suffer misfortunes on a frequent basis.
* DodgyToupee: In "Guess What's Coming to Dinner", his hair is revealed to be a wig. Hoss even comments on how obvious it is he's wearing a hairpiece before it comes off.
* NoCelebritiesWereHarmed: He sounds remarkably like Creator/PaulLynde.

!!Supernatural creatures

->Voiced by: Creator/RachaelMacFarlane

The goddess of chaos. She possesses the powerful Apple of Discord, a golden apple which can transform into any shape to perpetuate chaos. Grim used to have a crush on her during earlier episodes, but later changes his mind, claiming her to be a "psychopath". She is also in love with Hoss Delgado, who reciprocates but finds her to be too dangerous.
* AlphaBitch: Gave off the vibe of being stuck-up and rude in her debut episode.
* ArtEvolution: She looks quite a bit different in her second appearance. She looks different again in her third.
* ArtifactOfDoom: The Apple of Discord, a golden apple which can transform into any shape to perpetuate chaos (though Billy calls it a "magic banana").
* BareYourMidriff: Her attire leaves her navel uncovered.
* BigBad: In just about every episode she plays a major part in, she is the main villain.
* CharacterizationMarchesOn: She went from a flighty valley girl to a more insane trickster with a British accent.
* EvilBrit: She has a British accent and is one of the show's main antagonists.
* EvilMentor: Frequently uses Mandy as an agent for spreading chaos, though she always does it in secret after her first episode. She attempts to do the same with Billy at one point, only to find that he's ''too'' chaotic and unpredictable to manipulate effectively.
* ForTheEvulz: She's the Goddess of Chaos, which pretty much means it's her job to screw with the lives of mortals for fun.
* HotGoddess: Pretty attractive, and many characters, including Grim during "puberty", has showed interest in her.
* ImpossibleHourglassFigure: She has a curvaceous and beautiful body.
* JerkassGods: Lives solely to cause chaos and destruction.
* LaserGuidedKarma: Her schemes often end up biting her in the behind.
* LiteralSplitPersonality: {{Word of God}} confirmed if ''Underfist'' had gone to series, Eris would split herself into two different versions of herself (a good version and an evil version) after being heartbroken from her break up with Hoss Delgado as the two versions attempt to win back Hoss's love each in their own crazy and chaotic ways. You can see them during the closing credits.
* MsFanservice: She's a curvy woman in a revealing outfit.
* NoCelebritiesWereHarmed: Her appearance and personality are based on {{Music/Madonna}}.
* PhysicalGod: While she generally relies on her apple to cause chaos, she is shown capable of doing essentially anything on her own, but simply chooses not to because it's more fun to watch chaos unfold rather than cause it herself.
* RealityWarper: The ability to alter reality and make impossible things happen comes with the territory of being an evil chaos goddess.
* {{Trickster}}: Lives to screw with humanity.
* ValleyGirl: In her debut appearance. Eris's accent turning from a Valley Girl accent to a British accent may be a reference to Madonna, who started speaking in a British accent later on in her music career.
* WeCanRuleTogether: Offered it to Mandy in one episode. Mandy considered it but when told she'd be the "second most powerful person in the world", [[ThereCanOnlyBeOne she promptly refused.]]
* WomanInWhite: Wears a completely white toga and is one of the most prominent characters in the series.
* {{Yandere}}: Her reaction to being dumped by Hoss? Turn into a giant bug and eat him.


->Voiced by: Fred Willard

An old arch-enemy of Grim's since middle school, and a former school bully, Boogey played pranks on Grim throughout his school career. Boogey is, in fact, the Boogeyman himself, and can shapeshift in order to scare people.
* ArsonMurderAndJaywalking: He blames his inability to scare children on TV, video games, and the ''tuba.''
* BigBad: He is the main villain in ''Billy and Mandy's Big Boogey Adventure'' (interviews with Maxwell stated that ''[[Film/StarTrekIITheWrathOfKhan Wrath of Khan]]'' was what inspired him to use him since he appeared in only one episode). He was also indirectly responsible for the events in ''Wrath of the Spider Queen''.
* FauxAffablyEvil: He often acts warm and friendly, but is really nothing more than an egotistical jerk and bully.
* HumiliationConga: [[spoiler:The climax of ''Billy and Mandy's Big Boogey Adventure'' has him suffer a string of humiliating misfortunes, capped off with [[UrineTrouble a dog peeing on him]]. It is so too much for him that the epilogue states that he got completely traumatized for life.]]
* JadedWashout: He tends to boast he used to be way scarier than Grim in their middle school years, but nowadays he is just a second-rate monster that can't even scare one single child (except for Billy and Mandy's friend, [[TheChewToy Irwin]]).
* {{Jerkass}}: He is also unpleasant on a personal level, as he treats all other characters like dirt.
* LackOfEmpathy: Empathy is a completely foreign concept for him. He enjoyed humiliating Grim as a kid and as an adult he sees everyone else as a potential victim to break mentally in order to cower before him.
* LeanAndMean: He's skinny and really unpleasant.
* {{Pirate}}: He dresses as a pirate in ''Billy and Mandy's Big Boogey Adventure''.
* TheRival: He has a rivalry with Grim.
* SinisterSchnoz: He has a big pointy nose and is one of the bad guys.
* SmallNameBigEgo: He thinks he's the scariest being alive, but according to Grim he's somehow less scary than ''butterflies''.
* SmugSnake: He's self-absorbed and thinks he's better than everyone else.
* VillainousBreakdown: After the [[spoiler:aforementioned HumiliationConga, he's so shaken that he lives in fear for the rest of his life.]]
* WhyDidItHaveToBeSnakes:[[spoiler: Boogie's worst fear is people not finding him scary.]]
* WouldHurtAChild: Granted the kids he hurts onscreen are far from saints, but he doesn't care about that, he is fine with trapping, mind-raping, throwing into lava and enslaving them, because in his own words ''he really doesn't like children.''


->Voiced by: Creator/DavidWarner, later Martin Jarvis

A black-skinned supernatural being with green eyes who wears a business suit. He has the ability to shapeshift, with which he can create several tentacles from his back that can electrocute his victims or turn them into beings looking like himself. [[IJustWantToHaveFriends What Nergal desires most is having friends]], once stating that it is quite lonely in the center of the world. However, he gets better once he starts a family.
* AffablyEvil: He's generally polite, even around his victims.
* AntiVillain: He merely wants friends and doesn't understand how to achieve it, while still respecting their wishes and limits. When he feels accepted he is pretty nice.
* BeneathTheEarth: He lives in the Earth's core.
* TheCameo: ''Underfist'' features a brief scene where he's on a picnic with his wife and son.
* CharacterDevelopment: Starts off as an AntiVillain, but ends up becoming a friendly member of Billy's extended family who usually means no harm. This primarily came after he began a family of his own.
* CrazyJealousGuy: "Son, it's not about you liking a girl, or a girl liking you. What's important is that she can ''never get away from you''."
* CombatTentacles: He can sprout tentacles from his back to fight.
* DemotedToExtra: After marrying Aunt Sis, he didn't have any more episodes focusing on him, but instead of his son, Nergal Jr, and his quest for finding friends was quietly put down. It wasn't until the last season where he would get an episode selling pizzas.
* DubNameChange: To Orco (Orc) in the Latin American dub.
* EldritchAbomination: He's a black creature from the center of the earth with electric tentacles (some of which have ''mouths''), removable organs and the ability to turn [[WasOnceAMan people]] into members of his kind.
* EvilBrit: He's a dark supernatural being who has a British accent. It helps that both of his voice actors were British.
* GoodParents: He does his best to be a good father to Junior.
* HappilyMarried: He ends up marrying Aunt Sis and having a son with her.
* IJustWantToHaveFriends: His longing for friendship is PlayedForLaughs thanks to his mental immaturity, melodramatic behaviour and social ineptitude.
* InterspeciesRomance: With Billy's Aunt Sis, since he's a supernatural being and she's a human.
* LargeHam: He was originally voiced by ''David Warner'', this comes with the territory. Toned down a bit after Martin Jarvis took over.
* ShockAndAwe: Can electrocute people with his tentacles.
* ShoutOut: He is a reference to a Mesopotamian deity of the same name.
* StalkerWithoutACrush: He wanted Billy and Mandy to be his friends long before he was officially introduced to them.
* {{Yandere}}: He is not good with rejection.

[[folder:Nergal Junior]]

->Voiced by: Creator/DebiDerryberry

The son of Nergal and Billy's aunt Sis. As a result, he is Billy's first cousin.
* AscendedExtra: He became a reccuring character thanks to being on the same school as Billy and Mandy, and would be the protagonist of his own episodes, moreso than his father. From a meta point of view, is justified, as Nergal Jr was more relatable with the audience than his father was.
* {{Adorkable}}: Generally comes off as a fairly sweet, awkward kid when not violently attacking others.
* BeneathTheEarth: Like his father, he lives at the Earth's very core.
* BerserkButton: Do ''not'' call him a freak or say he's hideous. Seriously, just don't.
* TheCameo: ''Underfist'' features a brief scene of him on a picnic with his parents. He's the only one of the three who doesn't have lines.
* CheshireCatGrin: He often has a creepy-looking and mischievous grin.
* CombatTentacles: He's Nergal's son after all, so of course he'd inherit being able to sprout tentacles.
* CreepyChild: He is able to turn into almost anything and is extremely creepy. His true form (although it's rarely seen) is very horrid to see.
* CuteMonsterBoy: An adorable and dorky boy who happens to be a demon spawn. Unlike Irwin (who is also this), he's also kind of creepy.
* DubNameChange: To Orquito (Little Orc) in the Latin American dub, following his father translated name.
* EldritchAbomination: Even more so than his father; he can shapeshift, walk through walls, spawn bat-like imps from his body and freeze people in supernatural stasis.
* EyeGlasses: Just like Irwin, Junior's eyeglasses change shape depending on his expression.
* GlamourFailure: No matter what form he uses, he keeps his glasses, yellow eyes, sharp yellow teeth, and green tongue.
* HalfHumanHybrid: Half human, half demonic entity or whatever Nergal is (Jr could count as a demigod if one believes Nergal is the Mesopotamian god he's named after)
* IJustWantToHaveFriends: Unlike his dad, ''not'' played for laughs... [[ReverseCerebusSyndrome at first]].
* LonersAreFreaks: "Freak" is pretty much his nickname, but also his BerserkButton.
* NiceGuy: One of the kinder characters on the show, but also a severe {{Yandere}} for friendship.
* OneWingedAngel: His true form, which is so grotesque and deformed that it's rarely, if ever, seen onscreen.
* OnlyFriend: Billy is the only character who treats him like a person, though even he immediately freaks out upon seeing his true form.
* ShapeshifterDefaultForm: The form of the first kid he tried to befriend (and subsequently did away with when he was rejected).
* VoluntaryShapeshifting: He can change into different people.
* {{Yandere}}: Initially portrayed as violently attacking anyone who mistreated him, but becomes somewhat more passive in later episodes.

[[folder:Jeff the Spider]]

->Voiced by: [[CreatorCameo Maxwell Atoms]]

A man-sized spider that Billy hatched from an egg who quickly imprinted on Billy. Later tried to "grow up", with mixed results, and joined Underfist.
* {{Adorkable}}: A GiantSpider with a heart of gold and no desire beyond to be loved by his adopted father, Billy.
* BewareTheNiceOnes: As seen in "Spider's Little Daddy", and to a lesser extent ''Underfist''.
* GiantSpider: He's a spider the size of a man.
* GrowingUpSucks: He and Fred realize the downsides of being an adult in ''Underfist''.
* MisterSeahorse: He's able to reproduce asexually. It's unknown if this is a trait of all Underworld spiders of if it's entirely unique to Jeff.
* NiceGuy: Jeff is described by Mandy as being both "too nice" and "basically insane".
* SelectiveObliviousness: He seems completely incapable of understanding that Billy hates spiders, including Jeff himself, to the point of madness, despite the fact that Billy regularly beats him with anything he can get his hands on.
* ThoseTwoGuys: He is paired with Fred in ''Underfist'', which is strange considering the two had no interaction before that.
* WellDoneSonGuy: His only real goal in life is to really have Billy love him like a son. Of course, when your dad is violently terrified of you, that isn't going to be easy.

[[folder:Fred Fredburger]]

->Voiced by: C.H. Greenblatt

A dimwitted, pale green, bipedal furry otherworldly creature resembling an elephant with stubby horns and the tail of a devil. Ends up forming Underfist just via a drawing.
* AlliterativeName: His first and last name both being with the letter F.
* BreakoutCharacter: Maxwell Atoms even referred to him as such.
* CatchPhrase:
** "Yes!"
** "Fred Fredburger, Fred Fredburger, Fred Fredburger, Fred Fredburger, [[OverlyLongGag Fred Fredburger]], [[BrokenRecord Fred Fredburger]], [[MadnessMantra Fred Fredburger]]..."
* {{Cloudcuckoolander}}: Is primarily fond of nachos and spelling his own name "real good".
* TheDitz: Even Billy is smarter than him and that REALLY says something.
* DubNameChange: He is named Fredogodofredo in the Latin American dub.
* DumbassHasAPoint: His original idea for the Underfist team is originally dismissed by Skarr as "childish nonsense", but Jeff saw potential in the idea- that Earth needs defenders from all the threats the Underworld spews out.
* GrowingUpSucks: He and Jeff realize the downsides of being adults in ''Underfist''.
* FromNobodyToNightmare: [[spoiler:He becomes the Lord of Horror in the BadFuture]].
* {{Keet}}: He's a hyperactive, elephant-like monster.
* MommasBoy: He lives with his 'mama'.
* ThePollyanna: He has a positive and cheerful outlook on life regardless of what happens to him.
* PottyEmergency: "'''[[PunctuatedForEmphasis I HAVE! TO MAKE! POO-POO!]]'''"
* ThoseTwoGuys: He is paired with Jeff the spider in Underfist.
* TrademarkFavoriteFood: He really likes to eat nachos and frozen yogurt, yes!
* VerbalTic: Has a tendency to say "Yes!"

[[folder:Jack O'Lantern]]

->Voiced by: Creator/WayneKnight, Creator/MauriceLaMarche (video game)

The main antagonist in the Halloween special, ''Billy & Mandy's Jacked Up Halloween''.
* BeCarefulWhatYouWishFor: He wanted eternal life so that he could continue playing tricks on the people of Endsville forever. He got his wish and is subsequently forced to remain isolated in his cottage for eternity after Grim decapitates him as punishment for tricking him, only able to leave once a year on Halloween to pull his tricks.
* BigBad: He is the main villain in "Billy and Mandy's Jacked-Up Halloween".
* TheCameo: Subverted. He doesn't get screen time or lines, per se, but is briefly mentioned in ''Big Boogey Adventure'' during the trial scene, when Boogey lists off everyone who has stolen Grim's scythe.
* CynicismCatalyst: Having his head cut off and being shunned by the citizens of Endsville over the ages as a pumpkin headed freak left him rather embittered to say the least. Though he still pulls tricks on the people of Endsville once a year it's clear that he does it now out of revenge rather than his own amusement.
* DisproportionateRetribution:
** The members of his own town saw to it he was executed just because he didn't know when to stop pranking them. Pretty dark, given the silliness of the show in general. Demonstrated when [[spoiler: he's sent to the underworld. This is still a bad habit of his and got his pumpkin head squashed. So it was bound to happen sooner or later.]]
** His pranks ''were'' causing people injury; tricking a guy off a ''cliff''.
* DoNotTauntCthulhu: Initially it seems that he had [[DidYouJustScamCthulhu succesfully scammed Cthulhu]] by forcing Grim into giving him eternal life, [[SubvertedTrope however]], immediately afterwards he learns the hard way that pissing off a powerful supernatural entity can have [[OffWithHisHead dire consequences]].
* EvilIsHammy: He's voiced by Wayne Knight. Of course he's this.
* EvilLaugh: Has an evil laugh that he often makes while pulling pranks.
* HoistByHisOwnPetard: When Grim came to collect him the first time, he managed to stop him with a feather leading into the deal to give him immortal life. At the end of the special, Grim uses a feather to send Jack to the underworld.
* TheHyena: He treated everything in life as a potential joke to the extent that he laughed in his sleep. This did change however after his bitterness for losing his head made him more jaded and abrasive.
* InnocentlyInsensitive: Implied that, before decapitation, he didn't understand that he was hurting people or that people were growing sick of him, to the point of wanting to kill him. He just kept pulling pranks and making jokes with a happy smile and laughed himself to sleep, he thought he was being genuinely funny. Despite all that laughter he was causing himself, the town didn't find his harmful pranks funny.
* FromNobodyToNightmare: Started off as a self-centred but largely harmless trickster, then he gains immortality along with a [[TookALevelInJerkass mile long mean streak]] and then he gets his hands on Grim's scythe, unleashes the spirits of the Underworld and takes over Endsville in a single night.
* {{Jerkass}}: He is a trickster, playing pranks and tricks for amusement without caring who gets hurt in the process. He was also shown using it to get what he wanted, such as when he tricked Grim into giving him immortality.
* NearVillainVictory: When he gains Grim Reaper's scythe he easily captures Grim and later on easily outwits Mandy's attempts to defeat him with her own tricks. He only loses at the end when Irwin unexpectedly triggers his phobia with a knight costume which triggers a chain event that leads to the defeat of his army and himself collapsed, helpless with laughter.
* OffWithHisHead: Grim decapitated him after granting him eternal life.
* ThePrankster: Of the evil variety. He pulls pranks maliciously.
* PumpkinPerson: After a deal with Grim (returning his scythe in exchange for immortality), Grim cut off Jack's head. He then replaced it with a Jack-O' Lantern.
* PungeonMaster: After Jack captures Grim, and gets ready to [[OffWithHisHead decapitate him with his own scythe as revenge]], he starts letting out [[HurricaneOfPuns a whole series of head-related puns]]. Grim is understandably not amused.
* SillyWalk: Did this back when he was mortal. The fact that he doesn't do this anymore in the present day is a sign of how much his [[CynicismCatalyst isolation over the years have affected him]].
* StingyJack: A remarkably accurate retelling of the old folktale. While several details of the story were changed (such as Jack primarily being a trickster rather than an alcoholic and Grim Reaper being tricked out of his scythe rather than the Devil being trapped by crosses) the primary points of the story were largely kept the same.
* WhoWantsToLiveForever: "Three hundred and sixty-four days a year, I can't even go the the ding-dong grocery store to buy pudding. And do you know why?" Of course it's not so much living forever than "living forever with a pumpkin for a head".
* WhyDidItHaveToBeSnakes: He has a crippling fear of knights, specifically the one that was sent to execute him all those years back. When he believes said knight had returned for him he was too frightened to fight back despite having the Grim Reaper's scythe in his hands.

[[folder: Brain Eating Meteor]]

->Voiced by: Music/{{Voltaire}} (singing voice), Creator/JeffBennett (speaking voice)

A strange alien meteorite that arrives in Endsville in, ''Little Rock of Horrors''. His goal is to devour the brains of everyone he finds and enlists Billy ([[DisabilityImmunity who is brainless]]) to bring him fresh victims.
* AsideGlance: Briefly gives an annoyed half-lidded look towards the audience when his first attempts to get Billy to bring him brains nets him a box of half-eaten "Bran" cereal.
* AssimilationBackfire: What ultimately does him in when he eats Mandy's brain. In her own words, her brain turned out to be a bit too "[[TooSpicyForYogSothoth spicy]]" for him to handle.
* AstonishinglyAppropriateAppearance: His main body looks like a brain, reflecting the fact that brains are his TrademarkFavoriteFood.
* BrainFood: His entire shtick. Given that his main body looks like a giant brain, combined with the fact that he grows slightly in size every time he eats a brain implies his entire body is made up of the stuff.
* CombatTentacles: He has two of them which acts as his limbs. They're also the primary tools he uses to suck out a persons brain.
* DeathByGluttony: Devouring Mandy's brain leads to his demise when she takes over his body.
* EatsBabies: Has no qualms sucking out the brains of newborns, in fact he actually finds their brains particularly delectable.
* {{Expy}}: The title card of his episode, combined with his method of operation and his penchant for singing makes him a clear one to [[Theatre/LittleShopOfHorrors Audrey II]]. The Theatre version to be precise.
* EyeOnAStalk: A single one of these is effectively his face. [[BizarreAlienBiology It's capable of acting like a mouth]] and on several occasions he eats brains directly through this method.
* FatalFlaw: Gluttony. When he shrewdly surmises that Billy is likely hiding someone from him he eggs him to bring them to him despite the fact that he had already devoured the brains of everyone in Endsville and when he subsequently eats Mandy's brain his mind is promptly [[AssimilationBackfire taken over]] and he [[DeathByGluttony melts away screaming in fear and pain]].
* FauxAffablyEvil: Acts open and friendly towards Billy when they first meet so he could lure him close and eat his (non-existent) brain. Later on he promises to be Billy's best friend if he keeps bringing him brains and [[PragmaticVillainy has the lobotomized victims act as Billy's playmates to keep him happy and compliant]].
* FinalBoss: Returns as the last boss faced in the story mode of the video game. Complete with his VillainSong.
* KilledOffForReal: In the show, he effectively ceases to exist when Mandy's personality overrides his and takes over his body. It's worth noting that he's one of the only characters to be ''permanently'' killed off, seeing as the show is usually pretty liberal about killing characters and bringing them back to life for comedy.
* NearVillainVictory: Thanks to Billy's unwitting help, he succeeds in eating every single brain in Endsville, even Mandy's though that backfires on him. Even then it's clear that Mandy had inherited his HorrorHunger and has no qualms demanding Billy to bring her fresh victims.
* OhCrap: After eating Mandy's brain his iris slowly shrinks as he realizes too late that something had gone wrong.
* StarfishAliens: Resembles a giant brain encased in glowing green slime with a single eyestalk and two tentacles as limbs.
* VillainSong: He sings [[http://www.youtube.com/watch?v=2X09YmQ2wLE "Brains"]]. From his entire entrance in fact, all of his dialogue are lyrics of the song. It isn't until at the very end that he speaks outside of singing.
* ZombieApocalypse: A relatively benign example. When he eats someone's brains he effectively lobotomizes them in the process (causing their eyes to turn green) and they subsequently dance along mindlessly to his [[VillainSong song]].


->Voiced by: Creator/PhilLaMarr

A vampire that was Grim's childhood hero.
* BreakoutCharacter: Introduced as part of the old horror icons alongside Frankenstein's bride and the Wolfman in "Home of the Ancients". But thanks to Phil hitting the role so enthusiastically, he made more appearances, completely eclipsing the Bride and Wolfman, even having a [[spoiler: family connection to Irwin]]. He was even used for part of Cartoon Network's live action Halloween promos via a puppet.
* DaywalkingVampire: Except for "Fear and Loathing in Endsville" and a brief moment in his first appearance, he doesn't seem to be harmed by sunlight.
* {{Dracula}}: [[CaptainObvious Duh.]]
* DisappearedDad: [[spoiler: He is Irwin's grandfather and is inferred to have left the family when his son Dick was young.]]
* EatsBabies: Cooks and devours the young of a giant scorpion monster in "Fear and Loathing in Endsville", much to their mother's horror.
* {{Expy}}: Of ''Film/{{Blacula}}'', the joke being he bears his name despite not looking at all what most media make of him. For extra HilariousInHindsight, in the Blacula movie, Dracula is the one who turns Blacula.
* GrumpyOldMan: He's elderly and has a crotchety attitude.
* {{Jerkass}}: When the aforementioned scorpion monster expresses her shock at seeing him eat her children, his response wasn't very tactful.
-->'''Scorpion Monster''': My babies!
-->'''Dracula''': Well, maybe if you didn't make your babies so delicious, Dracula wouldn't have to eat them!
* JerkWithAHeartOfGold: On occasion proves to be capable of compassion despite his rude ways, such as sucking poison out of Grim or giving Irwin advice on accepting his monster heritage.
* JerkWithAHeartOfJerk: After Grim rescues Dracula in gratitude of discovering that he sucked out his poison in "Fear and Loathing in Endsville", Dracula offers to pay for their meal at the diner, but he is then walking away in the background, revealing his selfless offer to be a lie.
* LukeIAmYourFather: Grandfather, to be precise. [[spoiler:Namely, Irwin's.]]
* NoCelebritiesWereHarmed: His voice and mannerisms are based on Redd Foxx.
* OurVampiresAreDifferent: Yup. Not only is he both Redd Foxx and Blacula, but he (most likely) [[AccidentallyCorrectWriting coincidentally]] resembles the novel version of Dracula more than most interpretations.
* PsychopathicManchild: He's a vampire who often acts immature and puts others in danger to satisfy his selfish desires.
* ScrewPolitenessImASenior: He quite often uses his age as an excuse for his actions.
* ScrewThisImOutOfHere: When his wife beat him to a pulp (not knowing he could turn into a bat), once he was far away from her, he took off, in fear of her attacking him again.
* ThirdPersonPerson: He referred to himself as "Dracula" often.

[[folder:Nigel Planter]]

->Voiced by: Jake Thomas

A ''Literature/HarryPotter'' parody who resides at Weaselthorpe House at Toadblatt's School of Sorcery.
* AffectionateParody: Of Franchise/HarryPotter. Unlike Harry, who is relatively humble and fairly skilled as a wizard, Nigel has an enormous ego and is completely hopeless at magic. [[spoiler: He's eventually revealed to have close to no potential as a wizard at all.]]
* ArchNemesis: Lord Moldybutt [[spoiler: WOULD be his mortal foe except for that he's a real estate agent]].
* CasanovaWannabe: Uses incredibly cheesy pickup lines when flirting with Mandy, and later does the same with Herfefiny.
* TheChewToy: Nothing ever goes right for him.
* TheChosenOne: The wizard destined to defeat Lord Moldybutt. [[spoiler: In actuality, he's destined to become the CEO of Planter's Peanuts, and has no future as a wizard.]]
* DubNameChange: The Latin American dub was {{inconsistent|dub}} about this, giving him at least three different names:
** Barry Pecas (Barry Spuds)
** Orquito Pote (Little Orc Pot), probably got changed due to sharing name with Nergal Jr translated name. Probably not helped with how both share [[Creator/VictorUgarte the same voice actor in the dub]] to add an extra layer of confusion.
** Harry Popote (Harry Straw), a PunnyName similar to his inspiration. This one stuck for his two last appearances.
* HopelessSuitor: He tries to unsuccessfully woo Mandy and, after hitting puberty, Herfefiny Heferfefer.
* IneptMage: He's a horrible wizard and an even worse student.
* LetsMeetTheMeat: He's a partial-tongue, allowing him to talk to snacks.
* MeaningfulName: [[spoiler: He is the heir to a massive peanut conglomerate, which, while not ever referred to by name, is heavily implied to be Planter's Peanuts.]]
* {{Retcon}}: In his third appearance, it is revealed that his dad is still attending Toadblatt's School due to never graduating and generally being an even bigger failure than he is. By his final appearance, however, it is revealed that [[spoiler: his parents were the owners of an enormous peanut conglomerate.]]
* TheReveal: [[spoiler: He's unknowingly the heir to a billion dollar peanut conglomerate, explaining both his last name, his ability to talk to snacks and his incompetence as a wizard.]]
* ScarsAreForever: Lord Moldybutt gave him a scar when he was a child. [[spoiler: It later turns out to be a pen mark that can be easily rubbed off.]]
* SmallNameBigEgo: Prides himself as the greatest wizard in the world, but is generally seen as a joke until being kicked out of Toadblatt's entirely by the time of "Order of the Peanuts."
* SmugSuper: Has quite the ego about being the chosen one.
* SoapOperaRapidAgingSyndrome: Hits puberty and doubles in height sometime before the events of "One Crazy Summoner."
* TheDogBitesBack: In "Nigel Planter and the Chamber Pot of Secrets" Dean Toadblatts disguises himself as Lord Moldybutt and torments him the entire episode. At the end, he shrinks Toadblatt to the size of a golf ball and putts him to France.
* VagueAge: Appears to be around the same age as Billy and Mandy in his first two appearances, but then suddenly gets a growth spurt and a much deeper voice in his next appearance, making him appear to be in his mid teens.

[[folder:Dean Toadblatt]]

->Voiced by: John Vernon, Ronnie Schell ("Nigel Planter and the Order of the Peanuts")

The dean of Toadblatt's School of Sorcery.
* ButForMeItWasTuesday: When Nigel Planter tries to get even with him in his last appearance, he doesn't remember him. When asked about this, Toadblatt explains that he's tormented thousands of students every semester and can't be expected to remember all of them.
* DeanBitterman: He's your standard ill-tempered dean who has it in for everyone at the school.

[[folder:Lord Moldybutt]]

->Voiced by: John Kassir

A creepy man who's after Nigel Planter, [[spoiler:but only to inform him of his future as the head of a peanut conglomerate]].
* {{Expy}}: A blatant pastiche of Voldemort from the ''Harry Potter'' books.
* RealAfterAll: "Nigel Planter and the Chamber Pot of Secrets" ended with Lord Moldybutt at first appearing to really be a disguised Dean Toadblatt, but the very end of the episode shows that he actually does exist.
* TheScottishTrope: Saying his name causes objects to break. [[ButtMonkey Not even Moldybutt himself is immune to this]].

[[folder:Sir Raven]]

->Voiced by: Julian Stone

A raven that occasionally narrates episodes.
* CreepyCrows: Well, duh.
* DeadpanSnarker: A very LOUD snarker, too.
* LargeHam: "Let's watch a clip. [[SuddenlyShouting WATCH! A! CLIP!]]"
* LemonyNarrator: He's a narrator who snarks about the characters and the plot.
* GiantSpaceFleaFromNowhere: He just kind of... appeared in "Tricycle of Terror", then started to appear some more. The fans adore him, though, so it's not a big problem.
* GreekChorus: His role is to comment on the story as it going on.
* HiddenDepths:
** If "Tricycle of Terror" is to be believed, he has a soft spot for Billy.
** In another episode, he complains about his obscurity, implying that he's upset over his limited role in the show. Also, he can squirt cheese out of his armpits.
-->'''Sir Raven:''' And what of me? What happened to Sir Raven you ask? Well you ''didn't ask'' did you!? NOBODY CARES WHAT HAPPENS TO SIR RAVEN! '''''EVER!!!!!'''''
* PunctuatedForEmphasis: He has a tendency to punctuate his words to hammer in his point. "IMPORTANT! COMMERCIAL! MESSAGE!!!"
* QuintessentialBritishGentleman: Looks the part, but lacks the personality.
* TheStoryteller: He's often seen as some kind of narrator to the episodes featuring him.
* SuddenlyShouting: His specialty is to raise his voice without warning.
-->'''Sir Raven''': Alas, poor Billy, destined to walk the sepulchered streets of suburbia! A doomed husk of a child, do not cry for him! '''''DO NOT CRY!!!'''''

[[folder:Velma Green, The Spider Queen]]

->Voiced by: Creator/KariWahlgren

A spider-woman who holds a grudge against Grim for winning the title of Reaper instead of her.
* DiscOneFinalBoss: She is set up as the main antagonist of ''Wrath of the Spider Queen'' before Arachnotaur is revealed to be the real threat.
* EeriePaleSkinnedBrunette: She's a sinister person with dark hair and pale skin.
* HiveQueen: She can control all spiders.
* MyGodWhatHaveIDone: She instantly regrets her vendetta against Grim when she learns that the ballots he stuffed all had her name on them and that Grim had no intention of cheating to win the election.

[[folder:Arachnotaur, Spider God of Anger]]

->Voiced by: Creator/DeeBradleyBaker

The Spider God of Anger, who appears as a minotaur with the legs and abdomen of a spider.
* BigBad: He turns out to have been the one manipulating the conflict in ''Wrath of the Spider Queen'' by exacerbating Jeff and Velma's anger.
* SealedEvilInACan: He was imprisoned in a carton of chocolate milk before Billy freed him.


->Voiced by: Dave Wittenburg

An evil marshmallow bunny who is the main antagonist of ''Underfist''.
* BigBad: He is the main villain of ''Underfist''.
* FluffyTheTerrible: His name is rather cutesy, considering how vile he can be.
* {{Jerkass}}: He has no problem hurting and scaring people and also admits to being responsible for Hoss Delgado's hatred of monsters, Mindy becoming a witch, Billy being afraid of spiders, and Fred Fredburger losing his tusks.
* KillerRabbit: Even if he is a harmless-looking marshmallow bunny, he's still very dangerous and has amassed an army of candy monsters.