Ambiguously Bi: Sleeps with Lilith and is married to Yvette, but is shown to be attracted to and possibly in love with Linneus.
Fetishized Abuser: Atros is an unfaithful, neglective husband who sleeps with his courtesans. Up there, he comes across as just a massive jerk — the abuse part comes in his treatment of Linneus (Atros's main Love Interest), Lilith (who seems to have an unrequited crush on him), and his wife. The first and second he treats as his property and regards as dirty whores — and that's not counting how he makes sure the second knows the first means more to him whenever they are having sex or how much of a guilt-tripping, Entitled Bastard he is toward the first. The third he despises because of her immaturity. But, of course, he has Daddy Issues and is amazing at sex, so everything is forgiven.
Hair-Trigger Temper: He's shown to be very angry, throws objects across rooms, punches clients for getting violent (double standards) and, according to Claret, he blames the messenger when told bad news.
Jerk with a Heart of Gold: The flashbacks to his childhood show that he at least used to have a good side.
Pet the Dog: Punching Liard in the face over his mistreatment of Linneus.
Real Men Hate Sugar: grown that way, as even a lil' tot he reproached Linneus for having sugar with tea.
Sex for Solace: Possibly. Sleeps with Lilith, but makes sure she knows that Linneus means more to him.
Argent, Xanthe's bodyguard
Battle Butler: Atros' most trusted right-hand woman, wields a rapier.
Remy Dubois, maid
Hidden Evil: Only time will tell which way she actually falls. She doesn't look bad, oh no. But (apparently) following her brother to a brothel, failing to express joy or comfort in meeting him again, her arrival inspiring little but worry in him, and her sneaking into his room to declare her intentions of having that room kiiind of seem to point this way.
Twincest The woman Rory pictures while masturbating is Remy, his twin sister.
Rags to Riches: He was sold to the Teahouse as a cleaning servant at age 5 and arrives at the house literally in rags. 21 years later, Linneus is living in complete luxury as a courtesan, habitually receiving jewellery (and possibly other pricey gifts) from his clients.
Unlucky Childhood Friend: Poor Linneus has known Atros since his fifth birthday and obviously has been in love with him for years. So far, no dice.
Axis
All Girls Want Bad Boys: Exploited. He knows this all too well. Thus, he milks his ruggedly handsome looks, mixes it with his dandy-like clothes and earned his place that way as top earner of the house.
Berserk Button: It’s AXIS, not Alice. Then again, Rhys seems to step on Axis' Berserk Buttons with each step...
Buxom Beauty Standard: In the first book's bonus comic, makes it very clear he fancies Claret's rack. Further underlined in the off-site "Ask Axis" feature.
Hot-Blooded: He has some opinions and he's making a spectacle of them.
Jerkass: Although he seems more angry than really assholish. When he's not being an asshole, of course. Special mention goes to Rory, who seems to trigger Axis' jerkass-ness without fail.
Sex Slave: Subverted.Word of God confirms that he's the only one who's there as a genuine career man, and wants nothing more from his life if he can nap and sex all day long.
Tsundere: He is about as pure type A as it gets, with the default mood of moody. He goes from furious at the thought of being chosen by Rhys to furious at not being chosen by Rhys in the span of four whole panels. Print version gives a nice example of his dere side, which apparently only exists for a few minutes at a time, tops, and can only be seen after he's been worn down by lots and lots of smouldering sex.
Rory Dubois
Naïve Newcomer: He's clearly not used to this whole whoring business.
Sweet Tooth: Underlining his gentle character, he's rarely seen not making or offering someone cupcakes. Even after the other person has established that they do not in fact care for sweets.
Twincest The woman he pictures while masturbating is his twin sister, as revealed in recent pages.
Informed Flaw: She's supposed to be the lowest-earning courtesan in the house, but she's cute and well-endowed, has a bubbly personality, has excellent customer service skills and is happy to serve.
The Klutz: The cast page (as of Nov 2011), She may not be able to service you, but she can serve you tea. Or spill it all over you. Whatever.
The Pollyanna: She's capable of sulking, but mostly she's chipper.
Sweet Tooth: As of character list in November 2012, Voted most likely to eat all the cake.
Rich Bitch: Whether or not she actually has the money to be considered rich, Lilith certainly dresses the part and is the top female earner of the house.
Really Gets Around: On top of being engaged, he's also having it off with Axis and captain of guard Zephyr, and has hired Claret at least once. And of course he's known in-universe (to his fiancée as well) as a total village bike.
Character list as of November 2013: Voted most likely to have illegitimate children in the double digits. Also voted Prom King.
Rich Bitch: He doesn't even bother to feign to think of the feelings of the common rabble, and seems to actively refuse to call people below him by their correct names, whether it's to annoy Axis or show a stable boy his place.
Alistair Grayson Dorian Reed III
Jerk with a Heart of Gold: The way he talks to Rory seems very obtuse and even harsh — but the way he treats him other wise is very considerate and gentle.
Neat Freak: Everything must be clean and neat. Part of it seems to stem from his Word of God confirmed germaphobia.
Sacha: GILDAR! Gildar late! Gilder: Hey! How'd you find me? Sacha: Is mathematical. Gildar in not at all other whorehouse. Leave only this whorehouse. ... Surprise Gildar afford.
Killer Rabbit: Oh he's so tiny and fuzzy and angry! And now everyone is dead.
Professional Killer: Works as a team with Gilder. After a comical first appearance, his next appearance is helping Gilder to kill a wealthy gentleman.
Uke: played with. He sure looks the part — 5'4" and tiny all over with fluffy hair, big eyes and a tsundere TM pout. Yet his attitude is very, ahem, chili peppery, and the cast page dubs him (as of summer 2012) "voted most likely to try and top you in your sleep".
Others
Zephyr Langston, Rhys' captain of the Guard
Evelyn D'Ivore, Rhys' sister
Gloria Elizabeth Averill Buckley, Rhys' fiancee and Reed's cousin
Foreshadowing: After a meeting about their wedding, Gloria threatens that Rhys is free to continue laying half of the nation, but should he ever embarrass Gloria, she'll make his and "his cunt's" life a living hell.
Vann Ezra Brennan Bryson, Gloria's valet
Above the Influence: Very coolheaded. Also "voted mostly likely to stay single. Forever."
Yvette Atros, Xanthe's wife
Daddy's Girl: evident from how she appeals to Atros to spend more time home. Hint: starts with "Daddy says". Also "voted most likely to have a title Daddy bought for her".