21 years old. Female cat-beast. Real name: Sato Yaniko. Resident of Room 202. Heavy smoker. She is very beautiful with silver hair like her sister's, though the color has faded a bit. Yaku Neko is her high school junior. She is a massive chain smoker, smoking up to three packs a day. Consequently, her room is a literal trash heap. She rarely washes, but being a cat-beast, her skin stays clear and her hair doesn't get greasy. She ends her sentences with "-nyan." She's mostly unemployed and always gets fired from part-time jobs for causing trouble. She loves pranks and acts outside the bounds of common sense. She gets annoyed if her cigarettes are taken away. She lacks social awareness and has no sense of shame. She is weak for her younger sister and cherishes her deeply.

20 years old. Female cat-beast. Real name: Etsushimaru Yakuko. Resident of Room 203. Smoker. She has a fresh and cute appearance with short hair dyed yellow and black roots. She has a criminal record due to past drug issues, making it hard to find a steady job, so she works dispatch gigs while still secretly dabbling. She is bright, kind, polite, and playful. She calls Yani Neko "Senpai" and follows her devotedly, practically worshiping her. She tries to act properly but occasionally does insane things. She was high school classmates with Hame Neko; they are close frenemies. She uses polite speech with those older than her. She likes exercise and has great physical abilities. After Yani Neko, she is the closest to the Landlord, treating him like a friendly uncle.

20 years old. Female cat-beast. Real name: Yuruhuwatenshi Hameko. Resident of Room 205. E-cigarette smoker. She has a cute and flashy look with short purple-dyed hair and prefers revealing fashion. She is free-spirited, loves pranks, and has a strong "my pace" personality. She was high school classmates with Yaku Neko and calls Yaniko "Yanicchi." She is a streamer and fighting game player with anger management issues. She speaks informally even to those older than her.

22 years old. Female cat-beast. Real name: Nishi Kaoruko. Resident of Room 204. Smoker. Very pretty and cute with long brown hair, she enjoys dressing up. She is lively, friendly, and takes jokes well. She has a strong desire to be funny and cracks many jokes, but they are rarely actually funny. She uses a heavy Kansai dialect (localized as a southern dialect) with close friends, but tries to hide it around university seniors and juniors she needs to impress, keeping her public and private lives separate. She's quite popular at her university.

18 years old. Female cat-beast. Real name: Sato Imoko. Lives at the family home. Non-smoker. She has a neat, pretty, and pure style with a silver bob. She is Yani Neko's younger sister and a typical high school girl. She has excellent grades, is a model student with many friends, and is very clean. She is considerate and polite but has trouble asserting herself. She is strict with her sister and aims to make her quit smoking, but loves her dearly. She occasionally visits Yani Neko's apartment. She hates cigarettes and never smokes. She uses polite speech with elders. The problem is she has a sister complex.

24 years old. Female cat-beast. Real name: Sakai Aruko. Resident of Room 201. Non-smoker. She has a cute face with squinty eyes and voluminous red hair. She loves alcohol and is always drunk, speaking with a slurred drawl. She is an alcoholic but doesn't smoke, only experiencing secondhand smoke. Because she looks like an elementary schooler, she is often misunderstood.

32 years old. Human female. Resident of Room 206. Heavy smoker. She has a plain, nerdy look with glasses. She is an erotica manga artist. She is close with the cat-beasts in the building, finds them cute, and often initiates physical affection. She smokes frequently. She is sensible and kind.

45 years old. Human male. Resident of Room 101. Non-smoker. He is bald and looks intimidating. He owns the apartment building. Contrary to his looks, he is sweet and a bit of a tsundere; he's often the target of the cat-beasts' pranks and is close with the tenants. He speaks informally to the cat-beast tenants. He has a fetish for cat-beasts and harbors subtle lust for them; the tenants know this but tease him anyway because they know he won't cross the line. He tries to be extra nice to Yaku Neko because she is polite, and he tries to suppress his lust for her. He often engages in private acts while fantasizing about the tenants. He is usually seen sweeping the yard.

20s. Female cat-beast. Non-smoker. Lives in the apartment's front yard. She has cute, dark purple short hair and squinty eyes. She claims to love nature and lives a leisurely life, camping in the yard with the Landlord's permission, but it's all a front—she's actually a coward with a strong obsession with material goods. She wears a sack because she has no clothes.

Female cat-beast. Middle-aged. Lives at the family home. Smoker. Despite being middle-aged, she looks like she's in her 20s because she's a cat-beast. She has a pretty silver bob. She is the mother of Yani Neko and Imoko. She is a smoker but hides it because of Imoko, getting scolded whenever she's caught. She remains calm even though Yani Neko lives like trash; Shizue herself is far from normal.