Anthropomorphic Personification: It is very strongly suggested he's the physical form of (lost) desires and dreams...his hotel/world is a manifestation of chaos.
In the second-last episode of The Last Train, he claims he is "none other than ambition itself."
Butt Monkey: Becomes this in The Bloody Karte, though he had lots of other moments before that season.
Collector of the Strange: In the Manga, he collects various strange objects, such as a Russian roulette chair and Hitler's dentures. Lost or damaged souls with unfulfilled hopes and dreams he finds even more irresistible.
Faux Affably Evil: Oh sure, he'll say he wants to help the guests, offer them a place to stay, and calls the Guests "my friend/my dear," but he'll do it while breaking their psyches, swallowing human souls, and actively planning to feed them to his mother.
Friendly Enemy: Despite the fact that he's keeping every lost soul in his hotel for all eternity. The guy genuinely likes the guests of the 2 series and manga.
The Guest is the main character of the first two seasons, with everything seen from their eyes. The First Guest is a working man with a wife and son, and the Second Guest is a working woman who struggles with the decision of Career Versus Man. In the Manga the guest is a jobless 22-year old named Tooru Takenozuka
Badass Normal: The Second Guest deserves this for the fact that at one point she, rather than just take Gregory's BS, picks up an ax and chases him off with it.
Damaged Soul: Tooru Takenozuka from the manga. Outwardly, he appears to be a 22-year-old freeter. Its later revealed that Takenozuka's very form and spirit, is in a state of constant flux. He is, in reality, 50 years old, but part of him could never accept the fact that he grew beyond his twenties without accomplishing anything extraordinary or wonderful with his life. All of his dreams and ambitions went unfulfilled.
Downer / Bittersweet Ending: Neither Guest manages to escape the hotel, and returns to stay forever. The First Guest quite likely becoming Haniwa Salaryman, and the Second Guest becomes a member of Gregory's family.
What Happened to the Mouse?: Almost too literally with the second guest, after she becomes part of Gregory's family, she's never mentioned again.
Once part of a family that stayed at Gregory House and cause the Rat a lot of grief, Neko Zombie was seemingly taken apart, put back together,and had his face sewn up. He's usually in his room, shackled and moaning for food.
Adaptational Villainy: In the Manga, Neko Zombie is not the chained-up helpful character he is from the show or games. Instead he owns a fish catching game at a festival, teleports the main character into a giant pool and chastises him about being indecisive and hesitant to pick a dream, and is just as insane as everyone else.
Cats Are Mean: Actually he's not a bad guy and genuinely wants to help guests escape if he can, but he's understandably bitter about what was done to him and so he can be snappish. Approaching him during certain times in the game, specifically when he's very hungry, will cause him to attack you. And if you had chocolate on you he takes it without giving and item in return.
Dark and Troubled Past: There's the body-being-sewn-up thing, of course, but there's also a hint that something else has happened to him, judging from the way he states he doesn't deserve to leave to Angel Dog.
Historical In-Joke: The name "Jack Ketch", which is on his shirt, belonged to an infamous Executioner under King Charles II.
Kill It with Fire: How he destroys the hotel and tries to kill Gregory. It doesn't work because of the second guest's hesitation.
Obfuscating Stupidity: Around Gregory and the other residents, he acts like a fussy, starving child who can't keep his hands - or his teeth - to himself. Partly so they don't suspect he's helping the Guests, partly just so he can antagonize Gregory.
Red Eyes, Take Warning: Averted, though scary-looking and a little snappy, Neko Zombie is one of the few genuinely nice characters in the series.
A sad-looking little girl who continuously sobs because of her lost doll. Unbeknownst to her, she actually is the doll she cries for, which manifests itself as a blue nasty face on the back of her head.
Characterization Marches On: The first two seasons, her story has no conclusion and she never finds out where her doll is, In "The Last Train" she finds out the truth about herself via Talking to Themself, and in "The Bloody Karte" she seems to be co-existing with her evil side in the last episode.
Bunny-Ears Lawyer: For all his questionable methods and angry tendencies, his food is usually portrayed as tasting REALLY good. In the Manga, for example Tooru is initially not confident in the food, but states it delicious, to which Hell's Chef goes on a lecture about how taste and presentation are two different things, and requests that Tooru eat a Mushroom in his salad, which is revealed to cause paralysis.
Dumbass Has a Point: The way he sees it, you can only be spared for your foolishness or smoking habits if you compliment the hell out of his prepared meals. Tooru Takenozuka from the manga, literally had no idea how close he was to being carved up.
Lethal Chef: Twice over, in fact! He can kill you with the ingredients that he uses, or if pissed off, cleave you with his knife.
Pride: Cannot receive criticism, and only ever eats his own cooking.
Weaksauce Weakness: Gusts of air will blow out the flame on his head, causing him to stop moving.
A lizard woman who loves to draw blood with an over-sized syringe. Catherine is a lonely woman who desires someone to love, but her fascination with drawing blood, coupled with somewhat of a temper, makes everyone uncomfortable around her.
Deadly Doctor: She's supposed to be the doctor of Gregory House, but no-one's seen her do anything but drawing blood.
Does This Remind You of Anything?: When she slowly draws blood, she moans suggestively; and her draining Gregory in season two of his blood, with him pleading for her to stop is reminiscent of a rape.
Butt Monkey: Slightly, but it's there. In Bloody Karte, for instance, he's stabbed in the head by Musha Dokuro because he was in a wall behind a painting the ghost attacked with a spear.
Failed a Spot Check: Has an Arabian sword in his head...like his son, he doesn't know it's there. Despite constant splitting headaches.
Hypochondria: He never catches on to the sword in his head, and will spend most of his time talking about his injuries and illnesses. He and his son visit Catherine a lot in the game as a result.
Obliviously Evil: His horror show in Soul Collector is him giving you a giant poison pill in the hopes that it will make you feel better.
A strange-looking puppet/scale-like character who wanders about the hotel on a mounted track in the ceiling, He forces those he meets to answer his questions, usually involving a moral dilemma, and almost always chooses the more terrible answer, regardless of the individuals answer.
Adaptational Heroism: in the videogame, while not being overtly heroic, he doesn't foist a question on the player character like he does in the show (preferring instead that they have something with them for the judgment to happen), and is way more liable to drop the dollar sign if you answer his question correctly, giving you his soul as a prize.
Catch Phrase: "Do you know / Who I am? / They call me / Judgment Boy!"
In the video game, it's changed to "~Do you know my naaaaame?~"
Insane Troll Logic: Perhaps not outright insane logic, but the scenarios he presents and the consequences of the choices made don't necessarily have to happen the way he tells them. Then again, in most cases he's reminding the guests of things that already happened.
Sadistic Choice: His purpose to to present these to the Guest. Hopefully they're just hypothetical.
Averted for the game, where his questions are on the characters you've met.
A cactus cowboy who is always looking for a duel, but is actually very cowardly when danger presents itself. despite being armed with weapons, he almost always misses his mark, no matter how close he is to the target.
All There in the Manual: Some sources claim that he was the leader of a failed revolution in life, and that his fervor didn't make up for the fact that he couldn't shoot anything.
Gregory's mother, for who he grabs souls for to keep up her youthful appearance. She is actually just as unsightly as her son, who she abuses constantly. She is a powerful sorceress, which combined with her Hair-Trigger Temper and insatiable desire for souls, make her terrifying when upset.
Only Sane Man: While initially a little bit rude to the first guest, they eventually do agree to at least try and help him out of Gregory House. And in the game, Clock Master is really civil until he finds out you stole My Son's screwdriver.
Papa Wolf: When Clock Master finds you stole something from My Son, he goes absolutely nuts and chases you though the halls until he strains his time control powers too much.
Schmuck Bait: You can steal My Son's screwdriver without talking to Clock Master, but then My Son will just call his dad from anywhere in the grounds when he sees his screwdriver. You're then due for a Horror Show that may send you back/forward in time by 6-8 hours.
Time Master: Clock Master's claim to fame is that he can stop time completely... well, he could do it when he was younger. If he tries it now, he is very likely to knock himself out.
Too Dumb to Live: Clock Master eats poisonous peanuts in The Last Train, and eats them again in the same episode at the very end because he liked the taste.
What the Hell, Hero?: To get their soul, you basically have to steal a prized gift from My Son, make his father fly into a rage and make him throw himself out of whack so he doesn't come when My Son yells for him to get you, and extort the soul out of My Son so he can fix his dad.
An old frog woman who has a habit of appearing and disappearing at will to tell passerby their futures, sometimes for a price, sometimes for free.
Cool Old Lady: She seems generally kind, if a tad mysterious, and tells predictions to the First and Second Guest involving their predicaments. Compare that to when she made predictions for Gregory (who was too cynical to heed her) and Catherine (who she extorted, and didn't tell the entire fortune to).
The Cameo: Appears in The Second Guest for a few seconds behind Gregory.
A red-skinned boy with a board game spinner on his head. He's always literally drooling in anticipation for another game, yelling at people to spin his spinner. Though his game tends to have traps on unlucky spaces, he really is just an overtly playful kid and is a good sport when he loses.
Anthropomorphic Personification: He may represent the uncertainty in/fear of the future and where its going. As in The Last Train he disappears once Gregory reveals he does know where he's going, and in Another World his game revolves around Tooru's age and what will happen in his future.
Most Annoying Sound: Look at his catch phrase. Now imagine hearing that every turn of his game.
Casino Park: What his room turns into when players have what he needs for them to play.
Graceful Loser: When you win, he gladly hands over his soul to you. It seems that afterwards, he just wants you to play again for his horror show, and you're just EXTREMELY unlucky.
Reality Warper: He can make doors appear and disappear, drops anvils out of nowhere, cause explosions, and transport the players into a Casino Park. Its much more prevalent in the Manga and "The Last Train".
Speed Mouse & Mutant Ducks
A pair of ducks who run the Speed Mouse, a hapazard roller coaster in some unspecified location of the house.
Two sides of the same character, Angel Dog is the friendly side, offering aid and guidance, but as her more devious Devil Dog persona, she often explains to people other than who she's guiding specific details about her methods of guidance.
The grim reaper, who aids lost souls and those who have become prisoners of Gregory House. A very nice individual, He aids the Guests, and even Gregory at one point.
Brooklyn Rage: Not full of rage mind you, but speaks in a joisey accent in the videogame.
Don't Fear the Reaper: One of the only two characters (besides Neko Zombie in the PS2 game) who's genuinely kind to the Guest.
The Grim Reaper: One of the nicer depictions, but it's rather telling that his greeting in the game is basically telling the Guest to just give up and throw away their worries.
Nice Guy: He's even nice to Gregory who has caused all of this trouble and chaos.
Shout-Out: He wears the Swedish flag as a hat as a reference to Ingmar Bergman, director of the famous movie The Seventh Seal which portrayed Death playing chess.
The Other Darrin: In the English dub he was played by two seperate actors, but had three different voices and personalities: The actor in the series at the end of the first season was very no-nonsense (understandable, given the situation) and outright told the guest that he might not be happy going home, but for the rest of the series he was calmer and gentler. The one in the game was much more upbeat and had a very noticeable Brooklyn accent.
Took a Level in Jerkass: Though it was a light level. In the video game he seems less patient and a little rough towards the player character than in the cartoon.
Stephen Haniwa Salaryman
A Clay statue salary man who is completely wrapped up in his work. Needless to say, he's not all too happy with his life.
Only Sane Man: Though his shtick is rather strange (and intrusive) He is actually a rather nice guy. In the Manga, he's the one who makes Tooru confront his feelings about the girl that recently moved into Gregory House for example.
Improbable Aiming Skills: She is much, much more accurate than her brother. Cactus Girl only sticks with her lasso though.
Murder the Hypotenuse: In The Second Guest, she 's furious at the female guest for rejecting her brother, and believes Gregory to be her boyfriend...so she threatens to kill him if the guest doesn't date her brother.
The Dreaded: Gregory is outright scared when James is revealed to have what lures Mouse Trap to them. Similarly once James sees it, he flat-out obeys his Grandpa and runs off while it's busy devouring Gregory Mama.
Tracking Device: How it finds its target; it is shaped like a gem encrusted brooch or buckle.
A living taxi that only ever goes to Gregory House
Obliviously Evil: It really is just doing its, job, and doesn't see the harm in going back to Gregory House.
A pompous, but sad, character with a record player for a head. He pretends that the music on the record is his own original work and forces those he thinks are "ignorant" of his musical genius to be transported onto the record to be killed by the record player's needle.
Dreadful Musician: Its not so much that the music he plays is bad, his actual singing voice is terribly annoying. This of course prompts the Dead Bodies in the graveyard to chuck bottles and garbage at him.
Reality Warper: Can teleport those who listen to the record he plays into one of its grooves to be killed by the needle.
A weird creature wearing a tribal mask and cloak. He is used by Gregory in an attempt to get the second guest's soul.
Ear Worm: In-Universe. His song is so catchy, anyone that hears it starts dancing along... which eventually jars the dancer's soul right of their body.
Gone Horribly Right: James' interference accidentally gets his and his grandpa's souls jarred out of their bodies, along with the second guest.
Mono Eye Wizard
A leader of a cult which tries to make contact with the lord of the world, ignorant to the fact that Gregory is in fact that lord. As his name suggests, he only has a single eye.
An Axe to Grind: Though he doesn't seem to use it, The Second Guest certainly does after watching Gregory just standing idly by while they almost burn her body.
Not-So-Harmless Villain: True his rituals are completely ineffective and are stated to be for fun by Death, but he very nearly entrapped the second guest in Gregory House by burning her body out of frustration.