Characters / The Grim Adventures of Billy & Mandy

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The Main Trio

Voiced by: Greg Eagles

The Grim Reaper who is fated to be Billy and Mandy's "best friend" forever after losing a limbo contest to them.
  • Abusive Parents: 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.
  • Acquainted with Emergency Services: 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.
  • Affably Evil: Is remarkably polite when he isn't putting his scythe to work or getting bossed around by the title characters.
  • The Ageless: Exactly What It Says on the Tin.
  • And I Must Scream: 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.
  • Anti-Hero: He's this only when a greater evil threatens the world or Billy and Mandy.
  • Anti-Villain: He's not The Grim Reaper 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.
  • Badass Boast:
    • "You don't know who you're messing with, man! I am The Grim Reaper!"
    • 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)
  • Badass Longcoat: As expected of the Grim Reaper.
  • Badly Battered Babysitter: His general function in the show.
  • Beware the Nice Ones: 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.
  • Butt Monkey: A lot less than Billy, but he has his moments when he's near Mandy or a rival.
  • Can't Stand Them, Can't Live Without Them: On several occasions when he is given the opportunity to be free of Billy and Mandy.
  • Conditioned to Accept Horror: 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 having to spend time with Billy and Mandy, which he has to do every day anyway.
  • Crouching Moron, Hidden Badass: 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.
  • Dark is Not Evil: At the very least nowhere as evil as Mandy.
  • Deadpan Snarker: He makes a lot of death jokes and underworld puns.
  • Dem Bones: Grim is like this 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.
  • The Devil Is a Loser: 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.
  • Does Not Like Shoes: Never shown with shoes.
  • Don't Fear the Reaper: Downplayed; he's an Affably Evil Punch Clock Villain who can be scary when he's reaping somebody but is otherwise a nice guy.
  • Evil Has a Bad Sense of Humor: Even Mandy is sometimes taken aback by the macabre horror Grim finds delightful.
  • Four-Temperament Ensemble: The Melancholic
  • Grumpy Bear: Downplayed. He's only grumpy when he's in a bad mood. Mandy, on the other hand.
  • Glowing Eyes of Doom: Several times when he gets absolutely enraged.
  • The Grim Reaper: Obviously.
  • Heroic Comedic Sociopath: Death amuses him, like when he laughs during a show when a patient flatlines, something that even Mandy looked sad to see.
  • Heel–Face Turn: After making the deal with Billy & Mandy.
  • Hot-Blooded: Pretty often, actually.
  • Humanity Ensues: In "Night of the Living Grim". He gets better, though.
  • Hypercompetent Sidekick: This the reason why Mandy wants to keep him and ditch Billy.
  • Hypocritical Heartwarming: Quite a few times when it comes to Billy and Mandy. 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!
  • Hypocritical Humor: He often bluntly points out how stupid Billy is. And yet, it tended to hurt his feeling when Billy called him stupid for critisizing his favourite show.
  • I Am Big Boned: A variation in the comics. Grim isn't thin. He's "delicately boned".
  • I Call It "Vera": In "The Taking Tree", we learn that he calls his scythe "Jodie".
  • The Kirk: More or less trying to survive being stuck with two insufferable children.
  • Kissed Keepsake: After Eris is tricked into kissing Grim, he says he never washed his face before and won't start doing it now.
  • Mistaken for Pedophile: 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.
  • Multiple-Choice Past: 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 Hand Wave, Retcon or even ignore outrightnote .
  • No Respect Guy: Even in the underworld, he gets no respect for his many duties as Reaper.
  • Not So Above It All: He tends to get swept up in Billy and Mandy's antics pretty regularly.
  • Odd Friendship:
    • 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.
  • Only Sane Man Despite being an all-powerful supernatural being hanging around a suburban neighborhood, he is much more grounded and stable than every other character.
  • Parental Substitute: 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.
  • Physical God: He's the Grim Reaper, after all.
  • Punch Clock Villain: 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.
  • Rage Breaking Point: 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.
  • Reality Warper: With his scythe.
  • Really 700 Years Old: He was a little kid during the Stone Age.
  • Red and Black and Evil All Over: His Black Cloak is red on the inside.
  • Scary Black Man: His voice actor is black.
  • Screams Like a Little Girl: Depends on the episode
  • Shipper on Deck: He teasingly ships Billy and Mandy occasionally.
  • Sinister Scythe: Which can do just about anything...except whack the weeds in Skarr's garden.
  • Sociopathic Hero: He dosen't like conversing with humans, much less saving them.
  • Tragic Villain: Played for Laughs. He didn't become The Grim Reaper by choice, but because his parents wanted him to... sometimes. Afterwards, he became a Person of Mass Destruction. He also softens after the deal with Billy and Mandy.
  • Tall, Dark and Snarky: He is Exactly What It Says on the Tin.
  • Too Dumb to Live: 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.
  • Unexplained Accent: Grim's Jamaican accent. His grandmother also has one, and has a Jamaican look to her to boot.
  • Villain Protagonist: A surprisingly downplayed example, since he shows his evil side sporadically and often (but not always) after being provoked.
  • Villains Out Shopping: Whenever he isn't ordered to kill someone, he lives a perfectly normal life.
  • "Well Done, Son!" Guy: 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.
  • Willfully Weak: Deliberately avoids abusing his powers to prevent causing problems. Unfortunately for him, that's exactly what Billy and Mandy end up doing.
  • Would Hurt a Child: He's been shown planning ways of escaping his deal with Billy and Mandy, typically by killing them in unusual ways.


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: 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.
  • Acquainted with Emergency Services: 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 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.
  • All-Loving Hero: 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.
  • Ambiguous Disorder: 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.
  • Ambiguously Jewish: 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.
  • Annoying Laugh: And how!
  • Arson, Murder, and Jaywalking: Billy's three greatest fears are spiders, clowns, and the mailman, with the greatest fear of them all being a spider/clown/mailman hybrid.
  • Asskicking Equals Authority: 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 The Stinger of the episode.
  • Ax-Crazy: 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.
  • Beware the Silly Ones: 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.
  • Black Bead Eyes: One of the few characters on the show who has this eye style.
  • Bratty Half-Pint: He can sometimes become one.
  • Bumbling Sidekick: While he has moments of surprising insight or competence, he generally functions as this to either Grim or Mandy.
  • Butt Monkey: He gets a lot of physical abuse.
  • Chaotic Stupid: 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.
  • Cheerful Child: He rarely has outbursts of rage, but when he does, this goes away really fast.
  • Childhood Friends: He's known Mandy since they were toddlers.
  • Cloud Cuckoo Lander: He will spout stuff that makes no sense except to him and maybe Irwin.
  • Cordon Bleugh Chef: In an early episode he dreamt that he made cookie dough out of assorted junk food, then ate it raw because 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 what I call a sandwich!".
  • Crouching Moron, Hidden Badass:
    • He was able to take on an entire alien fleet by himself, and even Grim and 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 Irwin's plans with the macrame club.
    • He singlehandidly 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 helped Hoss Delgado fight a group of zombies with nothing but a stick.
  • The Ditz: His IQ is -5, being outperformed in the test by a shovel and two candy bracelets (they got a positive 17).
  • Drop the Hammer: His Weapon of Choice is a war hammer, which he is surprisingly skilled at wielding.
  • Dumbass Has a Point: Very commonly chimes in to point out the flawed logic in Mandy or Grim's thinking, only to be dismissed as an idiot.
  • Dumb Is Good: 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, his complete lack of self control and extremely destructive tendencies lead him to be arguably the most dangerous of the three.
  • Everyone Has Standards: Even he thinks Fred Fredburger is annoying.
  • Extreme Omnivore: 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.
  • Fiery Redhead: Only when he's angry.
  • Fluffy Tamer: His specialty is befriending supernatural horrors that help the trio out in a pinch.
  • Four-Temperament Ensemble: The Sanguine
  • Friend to All Living Things: Although in the case of spiders, he doesn't love them back.
  • Future Badass: 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 Billy we're talking about. It makes one wonder what did Mandy do to make Billy become this way...
  • Gag Nose: 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.
  • He-Man Woman Hater: 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 Billy is not worth that trouble.
  • Hidden Depths:
    • 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.
  • Idiot Hero: Far more traditionally heroic than Mandy and Grim, but also much more idiotic and twice as destructive.
  • Improbably Low IQ: -5. Again, a shovel and two candy bracelets are smarter than he is.
  • Informed Judaism: The Christmas episode states he's Jewish, but it's never brought up again.
  • Innocently Insensitive: 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.
  • Iron Buttmonkey: To the point that he could be considered The Chew Toy of the show.
  • Jerkass Ball: As with Mandy, Billy has his moments too.
  • Jerk with a Heart of Gold: He's somewhat insensitive and unempathetic but he does have his kind moments.
  • Jerkass Has a Point: In "Wrath of the Spider Queen" Billy delivers a massive Kick the Dog 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.
  • Keet: He's always excited.
  • Kindhearted Simpleton: Downplayed, while he causes a lot of trouble, it's more out of his stupidity rather than malice. He generally comes off as well-intentioned and kind.
  • Lack of Empathy: Especially apparent when interacting with his "son", Jeff.
  • Lethally Stupid: Everything Billy does within the show will inevitably result in mass destruction and chaos, especially when magical artifacts like Grim's scythe are involved.
  • Like Parent, Like Child: He's both stupid (like his father) and mentally unstable (like his mother).
  • Made of Iron: 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!
  • Major Injury Underreaction: 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.
  • Meaningful Name: His name means "desire".
  • The Mentally Disturbed: He does the unusual combo of being both moronic and completely insane.
  • Morality Pet:
    • For Mandy. When she's not bullying him or helping him for her own personal gain, she's treats him as a scolding mother would treat her son.
    • He's also one to Grim, who seems almost affectionate towards him at times.
    • He's one to Mrs. Claus in the Christmas Episode, 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.
  • The McCoy: Stupid and impulsive.
  • Obliviously Evil: 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 the true antagonist dangling spiders in front of Billy when Bill was a baby For the Evulz.
  • Odd Friendship: His two closest friends are an obscenely dark and anarchistic girl and the humanoid personification of death.
  • One-Man Army: He's occasionally shown to be almost disturbingly powerful when angry, to the point where even Mandy is terrified of him.
  • Only Friend: He appears to be the only person Mandy actively hangs out with.
  • Pink Girl, Blue Boy: The blue boy to Mandy's pink girl.
  • The Pollyanna: 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.
  • Rapid-Fire "Yes!": He would often respond with "yeahyeahyeahyeah..." when he's excited.
  • Red Oni, Blue Oni: The red to Mandy's blue.
  • Screams Like a Little Girl
  • She's Not My Girlfriend: Says this word by word when Grim assumed such about him and Mandy in the second episode.
  • Simpleminded Wisdom: He does this more often than he should, making you second guess his stupidity.
  • Smarter Than You Look: Make no mistake Billy is genuinely as stupid as he comes across but he's typically more tuned in to things than he appears.
  • Strong Family Resemblance: To his dad.
  • Token Good Teammate: Compared to Grim and Mandy at least which admittedly doesn't say much.
  • Took a Level in Dumbass: By the end of the show, Billy's become an Epic-Level dumbass.
  • Unstoppable Rage: 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.
  • Villain Protagonist: 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 Ax-Crazy. 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.
  • Why Did It Have to Be Snakes?: Hates spiders with a passion, which creates some rift between him and his spider-baby Jeff.

Voiced by: Grey DeLisle

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.
  • The Ace: 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.
  • Action Girl: She's the most consistently competent in a fight out of the three of them.
  • All Girls Want Bad Boys: She falls in Love at First Sight with a goth artist boy who Billy befriends in one episode. Her reaction is surprisingly adorable. The revelation that he's a poser makes her immediately lose interest in him.
  • Amoral Attorney: Her Halloween costume in one episode.
  • Anime Hair: Her hair sticks up at the back and curls a little, resembling devil horns.
  • Anti-Hero: Either a Nominal Hero or a Villain Protagonist.
  • Arbitrary Skepticism: 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.
  • Badass Normal: 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.
  • Beware the Quiet Ones: A stoic kid who is very sadistic.
  • Big Damn Heroes: Despite her goal on world domination, she saved the world multiple times.
  • Big Bad: Of The Grim Adventures Of The Kids Next Door.
  • Big Ol' Eyebrows: Has two big ones that cover her entire face.
  • Bright Is Not Good: She may be the inverted version of a Perky Goth. She wears brightly-colored clothes and has a Gothic personality.
  • Card-Carrying Villain: She makes no excuse for her being evil, and absolutely refuses not to be seen as anything but.
  • The Comically Serious: She's always overly serious, but is so, in a slapstick and humorous manner.
  • Creepy Child: 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.
  • Deadpan Snarker: Definitely.
  • Death Glare: In which intimidates anyone.
  • The Dreaded: Almost everyone get scared of her just by using her 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.
  • Emotionless Girl: 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.
  • Enfant Terrible: Young enough and psychopathic enough to qualify.
  • Even Evil Has Standards: She wants to rule the world and turn it into a dystopia, but she is not okay with cheating.
  • Even Evil Has Loved Ones: 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 sort of scared of her.
  • Evil Genius: She's able to manipulate almost every villain and monster for her own will, and God help you if you dare try to cross her.
  • Evil Hero: Played Straight.
  • Flanderization:
    • From simply an apathetic, snarky kid with a Hair-Trigger Temper and a bossy streak to an 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 Evil Genius who not only can pretty much fix or undo anything by just appearing on the scene, but owns everyone apparently.
  • Four-Temperament Ensemble: The Choleric
  • Flat-Earth Atheist: She is rendered immune to the Tooth Fairy's powers by revealing, to his face, that she doesn't believe in him.
  • Fluffy the Terrible: 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.
  • Gagging on Your Words: As revealed in "Sickly Sweet," Mandy is such a Jerkass that even something as simple as saying "please" is nearly impossible for her.
  • Goth: General consensus is that she's pretty much a Lone Psycho Goth, albeit one that dresses in an ironic fashion.
  • Goth Girls Know Magic: Played With. In contrast to her appearance she has a cynical and dark personality befitting a Goth, and does not have any inherent magic, but sporadically gains temporary supernatural and magical powers in episodes.
  • Greater Scope Villain: 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 Bad Future.
  • Guile Heroine: She can take down foes both mortal and immortal in seconds.
  • Hair Decorations: Wears a black headband.
  • Hates Being Touched: Do not touch her unless you wish to be bitten or punched.
  • Hidden Depths:
    • 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 it seems that Billy may actually have been killed by the Kraken.
  • Hijacking Cthulhu:
    • In a certain episode, a brain-eating alien monster with a familiar singing voice has been spending the whole episode being fed by Billy. When Mandy confronts it, it sucks out her brain.... but its aura immediately changes to resemble Mandy. Her only explanation is that she was 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, it takes on her appearance.
  • Horned Hairdo: Making her look fittingly demonic.
  • Hypocritical Heartwarming: She would never let Billy do any of the things that she does.
  • Improbable Weapon User: In the Cartoon Network game "The Fight Before Christmas", she uses a toy hammer, a toy plane, a dollnote , a fistful of marbles and a pan of popcorn as weapons against the evil toys overrunning Santa's workshop.
  • Informed Deformity: In My Fair Mandy, a skilled make-over artist was shocked by her appearance, at first mistaking her for an ugly tree stump.
  • Ironic Name: Her name means "adorable" or "lovable", despite her bitter and cynical attitude.
  • Iron Lady: Her ultimate goal in life is "[....] to do something important!" She eventually is elected president of the United States, and in the distant future, will rule the world.
  • Jerkass: Develops more and more 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."
  • Jerk with a Heart of Jerk: While she does do heroic actions like saving Billy from himself or whatever Monster of the Week they're up against, as well as saving the whole planet, Mandy will always have a selfish motive in mind no matter what — but...
  • Jerk with a Heart of Gold: ...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.
  • Karma Houdini: Rule of Funny usually dictates that she gets off scot-free — but there are a few occasions where she's outwitted and beaten.
  • Lack of Empathy: Whatever empathy she has is locked away in the cold dark recesses of her soul.
  • Little Miss Badass: Wears pink, is blonde, snarks almost constantly, and makes the Grim Reaper her personal bitch in the first episode.
  • Little Miss Snarker: This line pretty much exemplifies it:
    "Power tools in the dark? Darwin should be paying you two goons royalties."
  • Madden Into Misanthropy: 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 Billy every single day of her life.
  • Manipulative Bitch: She manipulated the Grim Reaper, Eris, Hoss, and sometimes even Irwin to do her bidding.
  • Noble Demon: She's The Dreaded, brooding, anti-social and occasionally evil but she's also loyal and stays close to her friends, always keeps her word and never cheats.
  • The Noseless: But she does have nostrils.
  • Not So Stoic: Some things can get under her skin, if rarely. Even she wasn't immune to being called ugly.
  • Odd Friendship: She willingly hangs out with Billy, despite the two of them being polar opposites.
  • Off Model: She looks decidedly... wrong in Underfist.
  • One-Winged Angel: Her future self from the episode, "Mandy the Merciless" where she is a giant worm.
  • Only Sane Woman: Trades roles with Grim, depending on the episode.
  • Perky Goth: Completely Inverted; she dresses like a standard little girl, but embodies the Lone Psycho Goth stereotype.
  • Perpetual Frowner: 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 Reality-Breaking Paradox.
  • Pet the Dog:
    • She will occasionally meditate on the possibility that she actually cares about Grim and Billy...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).
  • Pink Girl, Blue Boy: The pink girl to Billy's blue boy.
  • Pink Means Feminine: Averted. Mandy usually wears a pink dress, but she isn't that feminine.
  • Pragmatic Villainy: 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 Monster of the Week, but only because the world is hers and she won't let anyone else take it from her.
  • Psychotic Smirk: By way of Early Installment Weirdness, 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!".
  • Red Oni, Blue Oni: The blue to Billy's red.
  • Slapstick Knows No Gender: Though rarer than with Billy, she's not immune to physical comedy. Whether that's being burned to a crisp by Cerberus in "Mandy Bites Dog", or being covered in snot twice after Grim sneezes on her in "Night of the Living Grim".
  • Sociopathic Hero: She enjoys people's pain and is one of the main protagonists.
  • The Spock: Intelligent and deadpan.
  • The Stoic: She never smiles fully at all. It's for the best.
  • Sugar and Ice Personality: She is actually shown to be somewhat caring and even passionate in some episodes.
  • Tiny Tyrannical Girl: In fact, almost everyone in the show is afraid of her.
  • Token Evil Teammate: The only hero who's more evil than a demon from the underworld.
  • Tomboy with a Girly Streak: 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.
  • Took a Level in Jerkass: Mandy became more hostile and disrespectful towards her friends in later seasons.
  • Unsympathetic Comedy Protagonist: She has no positive qualities beyond being intelligent and competent, both of which she uses to make the world a bad place.
  • Villains Out Shopping: Whenever she isn't scheming, she's just spending time, with Grim and Billy at their house.
  • Villain Protagonist: When you make the personification of death look like a nice guy in comparison...
  • When She Smiles...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.
  • Why Did It Have to Be Snakes?: 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.
  • Wise Beyond Her Years: She may be a real bitch but she's EASILY the smartest character on the show.
  • You Go, Girl!:
    • 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. Pud'n won.

Other Characters

Voiced by: Vanessa Marshall

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.
  • Abhorrent Admirer: Towards Mandy. All of the occasions of her reciprocating his feelings were either due to magical influence or being unconscious.
  • Accidental Hero: 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 The Woobie due to his relentless suffering.
  • Black and Nerdy: Though he's not that smart.
  • Black Best Friend: To Billy.
  • Breakout Character: Gets steadily more appearances until becoming the main character of Underfist.
  • Butt Monkey: Gets a lot of punishment along with Billy.
  • The Chew Toy: He is pretty much the Kenny variant of this show.
  • Dark is Not Evil: 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).
  • Dogged Nice Guy: To Mandy.
  • Eye Glasses: His glasses will sometimes contort to his expression. His eyebrows will also overlap his glasses sometimes.
  • Four-Temperament Ensemble: The Phlegmatic
  • Half-Human Hybrid: 1/2 Mummy, 1/4 Vampire, and 22/7 nerd.
  • Jerkass Ball: He can even be the villain of an episode if the situation calls for it.
  • Mad Love: Keeps a huge crush on Mandy, no matter how many times she rejects him.
  • Our Vampires Are Different: Very much so. Just read the rest of this entry.
  • Red Eyes, Take Warning: In Underfist. And that's when Bun-Bun realized he was screwed.
  • Stalker Shrine: In the Halloween special, it is shown that he has one where hundreds of Mandy's eyes glare at him. It is one of the most disturbing things in the special.
  • Stalker with a Crush: To Mandy.
  • Straw Loser: 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).
  • Super Power Lottery: Irwin's being a Half-Human Hybrid has given him several powers in Underfist such as: Flight, Hand Blast (called Mummy's Curse), Mummy Wrap, Super Strength and Voluntary Shapeshifting.
  • Took a Level in Badass: In Underfist.
  • Used to Be a Sweet Child: 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 Enfant Terrible at birth before his dad turned him around.
  • Verbal Tic: ...yo. Seems inherited; his dad calls people "dude", and his grandmama calls her loved ones "baby".
  • Vocal Evolution: 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.
  • With Friends Like These...: 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 his first thought was to use it to brainwash Mandy and go on a forced date.


Billy's father and Gladys' husband.
  • Autocannibalism: In one episode, while picking his nose, he pulled his own brain out through his nose and proceeded to eat it.
  • Bumbling Dad: Like his son, he often doesn't care about anything and has a small IQ.
  • Closer to Earth: While he is dumber than Gladys, he is not as prone to fits of nervousness like she is and is quite relaxed around Grim.
  • Crouching Moron, Hidden Badass: A former Navy SEAL.
  • The Ditz: Billy got more than just his looks. This applies even before he Took a Level in Dumbass considering he didn't seem to notice that Grim was actually the Grim Reaper!
  • Fat Idiot: He's not a stupid as his son, but he's close.
  • Flanderization: He actually wasn't particularly 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.
  • Happily Married: To Gladys.
  • Hidden Depths: In his youth, he was apparently smart enough to get accepted into Harvard University. 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.
  • Mr. Vice Guy: He's overall a decent guy, even if he's disgusting and rather stupid.
  • Noodle Incident: He once dressed up like Sasquatch, kidnapped Billy and did something to him that left him with "emotional scars". This might explain why his wife thinks she's had an affair with Sasquatch too.
  • Only Sane Man: In the early episodes, before the above mentioned Flanderization, he was this compared to his wife and son.
  • Red Oni, Blue Oni: The blue to Gladys' red.
  • Strong Family Resemblance: He's an older, fatter Billy with a pompadour.
  • Took a Level in Dumbass: Starts out as reasonably intelligent, but eventually becomes much dumber.
  • Ugly Guy, Hot Wife: His wife is considered quite attractive by some while he looks almost exactly like an older, fatter version of Billy.

Voiced by: Jennifer Hale

Billy's mother and Harold's wife.
  • Ambiguous Disorder: She's implied to be the source of Billy's psychopathic outbursts.
    Harold: Did someone forget to take their medicine today?
  • Anger Born of Worry: Her angry side was born from her worry of Grim, and she learned to not fear him, but destroy him.
  • Doting Parent: She is a caring but overprotective mother to Billy.
  • Fiery Redhead: She can even make Grim run away in terror.
  • Happily Married: To Harold.
  • Mama Bear: 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!
  • Noodle Incident: Apparently, Gladys has had some sort of...less than wholesome liaison with Sasquatch, which is referenced in an episode wherein Billy grows a whole lot of hair and Gladys mistakes him for Sasquatch. Though given this strange little "hobby" her husband has, it's possible that it was actually him in disguise.
    Gladys: (attacking Billy thinking he's Sasquatch) I TOLD YOU IT IS OVER BETWEEN US!
  • Properly Paranoid
  • Red Oni, Blue Oni: The red to Harold's blue.
  • Self-Serving Memory: She remembers the circumstances that led her to leave a little differently than they actually happened.note 
  • Stepford Smiler: 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.
  • Super OCD
  • Twitchy Eye: She has this whenever something goes wrong or the supernatural happens.
  • Ugly Guy, Hot Wife: She is considered quite attractive by some, while Billy's dad, Harold, looks almost exactly like an older, fatter version of Billy.
  • Women Are Wiser: Subverted. While smarter than her husband, she's also mentally unstable and prone to fits of homicidal rage (which she passed t her son.)


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.
  • Alpha Bitch: Gave off this vibe in her debut episode.
  • Always Chaotic Evil: The only person who's more chaotic than her is Billy, and the only person more evil than her is Mandy.
  • Art Evolution: She looks quite a bit different in her second appearance. She looks different again in her third.
  • Artifact of Doom: The Apple of Discord, a golden apple which can transform into any shape to perpetuate chaos (though Billy calls it a "magic banana").
  • Bare Your Midriff
  • Big Bad: Of just about every episode she plays a major part in.
  • Evil Mentor: 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.
  • For the Evulz: She's the Goddess of Chaos, which pretty much means it's her job to screw with the lives of mortals for fun.
  • Hot Goddess
  • Impossible Hourglass Figure: She has a curvaceous and beautiful body.
  • Jerkass Gods: Lives solely to cause chaos and destruction.
  • Literal Split Personality: 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.
  • Ms. Fanservice: She's a curvy woman in a revealing outfit.
  • No Celebrities Were Harmed: Her appearance and personality are based on Madonna.
  • Physical God: 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.
  • Reality Warper: Comes with the territory of being an evil chaos goddess.
  • Trickster: Lives to screw with humanity.
  • Valley Girl: 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.
  • We Can Rule Together: Offered it to Mandy in one episode. Mandy considered it but when told she'd be the "second most powerful person in the world", she promptly refused.
  • Woman in White: Wears a completely white toga.
  • Yandere: Her reaction to being dumped by Hoss? Turn into a giant bug and eat him.

    Hoss Delgado
Voiced by: Diedrich Bader

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.
  • Accidental Misnaming: In Underfist, he keeps getting Irwin's name wrong. He calls him "Irving", "Urkel", and "Ivan". He correctly calls him "Irwin" while saving him from the giant pumpkin-headed candy monster.
  • Art Evolution: 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.
  • Anti-Hero: He believes that all monsters are a threat, which causes him to murder any monster he ever sees, even innocent and harmless ones.
  • Awesome Mc Coolname: His name is a pretty good indicator of his outrageous badassery.
  • Big Brother Mentor: Acts as a rather half-assed one to Billy in a few episodes, and Irwin in others.
  • Bunny-Ears Lawyer: He's a tad eccentric and not very bright, but he is a damn good spectral exterminator.
  • Characterization Marches On: 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.
  • The Comically Serious: His lines are almost always ridiculous, but delivered in a completely serious Badass Baritone.
    "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"
  • Dating Catwoman: His relationship with Eris.
  • Dark and Troubled Past: 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.
  • Dumb Muscle: He's far from the brightest bulb, but is an excellent fighter.
  • Empowered Badass Normal: 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.
  • Eyepatch of Power
  • Expy: Of Snake Plissken and Ash at the same time!
  • Go-Karting with Bowser: Despite his hatred of Grim, he's perfectly willing to pal around with him when the situation calls for it.
  • Good Is Not Nice: 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.
  • Hammerspace: Where he keeps all the random attachments for his hand (his chainsaw, goo cannon, crossbow that fires a chainsaw).
  • Hero Antagonist: 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.
  • Hidden Depths: 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.
  • 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.
  • One-Man Army: Generally has an easy time taking out hordes of supernatural monsters, though he has quite a bit more trouble dealing with Eris.
  • Perma-Stubble: Pretty much a given, considering who he's based on.
  • Pre Ass Kicking One Liner: When he isn't belting out complicated and bizarre metaphors that don't apply to the situation, he's delivering really campy one liners.
  • Sour Supporter: Did not want to be part of Underfist, but President Mandy ordered him; by the end, he's warmed up to the idea.
  • Swiss Army Appendage: 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.
  • Tank Goodness: 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.
  • The Stoic: Most of the time.
  • Tragic Hero: 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 Hero Antagonist.
  • Took a Level in Badass: In the past. He used to be a loser like Irwin, until he became the Hoss we know.
  • Took a Level in Dumbass: He was never particularly smart, but Underfist takes it a step further.
  • Top-Heavy Guy: 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.
  • Van Helsing Hate Crimes: He's a spectral exterminator, hunting monsters for a living. The problem being that not all of them are bad; Grim, for instance. He even took out a bunch of lawyers because 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 "one-eyed weirdos", in Skarr's case). He also hesitates in joining Underfist because of this. 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: Ivan is a mummy-vampire? That means you lied to me twice when you said you weren't a monster!
  • The Worf Effect: Very present throughout Underfist.

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.

    General Skarr

Voiced by: Armin Shimerman

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.


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.
  • Alpha Bitch: A much younger Alpha Bitch, 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!"
  • Asshole Victim: Thankfully, she's also one of the show's regular victims of whatever supernatural power is at hand in the episode.
  • Bratty Half-Pint: Falls right into this category.
  • Disproportionate Retribution: 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.
  • Evil Redhead: She has ginger colored hair and is a nasty, downright obnoxious Alpha Bitch.
  • 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 Genki Girl in contrast to Mandy's Emotionless Girl; Mindy is shallow, spoiled, and stupid while Mandy is dark, cynical, and intelligent.
  • Genki Girl: A rare evil variant.
  • Jerkass: She constantly torments Mandy in a verbal manner (In fact, her catchphrase is "LOSER!") and taking it all in stride.
  • Heel–Face Turn: At the end of "Underfist".
  • Licked by the Dog: A subversion in one episode in which this literally happens and she responds by acting even worse than usual!
  • Popular Is Dumb: "But as beautiful and popular as I am, I bet there are some people who've never even heard of me: people in countries like Paris or Toronto, or in cities like Africa."
  • Rich Bitch: She is the evil, rich and spoiled queen bee of the school.
  • The Rival: For Mandy, at least.
  • School Uniforms Are the New Black: Is almost always seen in her school clothes.
  • Took a Level in Badass: Twice in a row; in both "Wrath of the Spider Queen" and "Underfist".


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.
  • Beware the Nice Ones: 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.
  • Butt Monkey
  • Brown Bag Mask: 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.
  • In Touch with His Feminine Side: He's weak, completely non-aggressive, loves fluffy pink bunnies, and cries at the drop of a hat.
  • Raised by Wolves: 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.
  • Berserk Button: Don't talk bad about his mom, especially if it causes her to cry right in front of him.
  • The Bully: He is often seen tormenting Billy, Irwin, or other kids.
  • Even Bad Men Love Their Mamas: He's very defensive of his mother.
  • Evil Redhead: Has red hair and is a bully.
  • Heroic Sacrifice: Saves the world from alien invaders by using the explosive chip in his head. He manages to bully people without a head.
  • Jerk Ass: To most kids, but primarily to Billy, Irwin and Pud'n.
  • Jerk with a Heart of Gold: In the episode where he and the rest of the cast fight off aliens, 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.
  • Real Men Wear Pink: He loved to sing showtunes. In "Tricycle of Terror," he expresses a desire to be on Broadway.


Voiced by: David Warner, 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. 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.

    Nergal Junior

Voiced by: Debi Derryberry

The son of Nergal and Billy's aunt Sis. As a result, he is Billy's first cousin.
  • Adorkable: Generally comes off as a fairly sweet, awkward kid when not violently attacking others.
  • Beneath the Earth: Like his father, he lives at the Earth's very core.
  • Berserk Button: Do not call him a freak or say he's hideous. Seriously, just don't.
  • Cheshire Cat Grin: And how!
  • Combat Tentacles: He's Nergal's son afterall.
  • Creepy Child: 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.
  • Cute Monster Boy: An adorable and dorky boy who happens to be a demon spawn. Unlike Irwin (who is also this), he's also kind of creepy.
  • Eldritch Abomination: 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.
  • Eye Glasses: Just like Irwin, Junior's eyeglasses change shape depending on his expression.
  • Glamour Failure: No matter what form he uses, he keeps his glasses, yellow eyes, sharp yellow teeth, and green tongue.
  • Half-Human Hybrid: 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)
  • I Just Want to Have Friends: Unlike his dad, not played for laughs... at first.
  • Loners Are Freaks: "Freak" is pretty much his nickname, but also his Berserk Button.
  • Nice Guy: One of the kinder characters on the show, but also a severe Yandere for friendship.
  • One-Winged Angel: His true form, which is so grotesque and deformed that it's rarely, if ever, seen onscreen.
  • Only Friend: Billy is the only character who treats him like a person, though even he immediately freaks out upon seeing his true form.
  • Shapeshifter Default Form: The form of the first kid he tried to befriend (and subsequently did away with when he was rejected).
  • Voluntary Shapeshifting
  • Yandere: Initially portrayed as violently attacking anyone who mistreated him, but becomes somewhat more passive in later episodes.

    Aunt Sis

Voiced by: Grey DeLisle

Harold's sister and Billy's Aunt, who later marries and starts a family with Nergal at the center of the Earth.
  • Everyone Calls Him "Barkeep": 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.
  • Happily Married: To Nergal.
  • Maiden Aunt: Before marrying Nergal. Gladys explicitly calls her a spinster when explaining to a curious Billy as to why she "ain't got nobody". Played for Laughs 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"

    Jeff the Spider

Voiced by: 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 Giant Spider with a heart of gold and no desire beyond to be loved by his adopted father, Billy.
  • Beware the Nice Ones: As seen in "Spider's Little Daddy", and to a lesser extent Underfist.
  • Female Monster Surprise: In "Jeffy's Web".
  • Giant Spider: The size of a man.
  • Growing Up Sucks: What he and Fred realize in Underfist.
  • Nice Guy: Jeff is described by Mandy as being both "too nice" and "basically insane".
  • Selective Obliviousness: 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.
  • Those Two Guys: With Fred in Underfist. Which is strange considering the two had no interaction before that.
  • "Well Done, Son!" Guy: 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.

    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.

    Jack O'Lantern

Voiced by: Wayne Knight

The main antagonist in the Halloween special, Billy & Mandy's Jacked Up Halloween.
  • Big Bad: Of the first Halloween special.
  • The Cameo: 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.
  • Disproportionate Retribution:
    • 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 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.
  • Evil Is Hammy: He's voiced by Wayne Knight. Of course he's this.
  • Evil Laugh
  • Hoist by His Own Petard: 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.
  • The Hyena: 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.
  • Innocently Insensitive: 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.
  • Freudian Excuse
  • Jerkass: He is a trickster, playing pranks and tricks for amusement. He was also shown using it to get what he wanted, such as when he tricked Grim into giving him immortality.
  • Off with His Head!: Via Grim
  • The Prankster: Of the evil variety.
  • Pumpkin Person: 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.
  • Pungeon Master: After Jack captures Grim, and gets ready to decapitate him with his own scythe as revenge, he starts letting out a whole series of head-related puns. Grim is understandably not amused.
  • Who Wants to Live Forever?: "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 then "living forever with a pumpkin for a head".
  • Why Did It Have to Be Snakes?: 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.


Voiced by: Phil LaMarr

Irwin's grandmother, more commonly known as "Grandmama."


Voiced by: Phil LaMarr

A vampire that was Grim's childhood hero.

    Nigel Planter

Voiced by: Jake Thomas

A Harry Potter parody who resides at Weaselthorpe House at Toadblatt's School of Sorcery.
  • Arch-Nemesis: Lord Moldybutt WOULD be this except for that he's a real estate agent.
  • The Chew Toy: Nothing ever goes right for him.
  • Let's Meet the Meat: He's a partial-tongue, allowing him to talk to snacks.
  • Scars Are Forever. Lord Moldybutt gave him a scar when he was a child... except not since it's just a pen mark and gets rubbed off fairly easily.
  • Small Name, Big Ego: 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."
  • Soap Opera Rapid Aging Syndrome: Hits puberty and doubles in height sometime before the events of "One Crazy Summoner."

    Sir Raven

Voiced by: Julian Stone

A raven that occasionally narrates episodes.