Yaniko

Yaniko Satou (佐藤ヤニ子, Satō Yaniko), also known by her nickname Yanineko (ヤニねこ), is the main protagonist of the Chainsmoker Cat manga and anime.

Her defining characteristic—and the source of the humor surrounding her—is her addiction to smoking. Beyond that, her life is a bit of a disaster: her apartment is constantly filthy and filled with trash; she is unemployed and struggles to hold down a job whenever she does find one; her social circle is full of people with unhealthy vices; and so on.

She has a sister named Imoko who worries about her but also tries to distance herself so as not to tarnish her own reputation as a student.

Appearance

Yaniko Satou is a cat-girl beastfolk in her twenties with short, messy silver-green hair, with silver-green pointed feline ears, with black tip on her left ear with pink interiors, two silver hoop earrings stacked together on her right ear, and dull amber eyes that often reflect her lethargic demeanor; she sports a slim figure with a notably large bust that is usually concealed beneath baggy, stained clothing—most commonly a loose, off-white V-neck T-shirt paired with oversized dark sweatpants and tan crocs—while her silver-green cat tail with a black tip trails behind her. Despite this disheveled everyday look that matches her squalid lifestyle and chronic nicotine addiction, she is actually considered a beauty—though most people only notice it on the rare occasions she cleans herself up and stops smoking.

Personality

Lazy, hedonistic womanchild, completely prioritizes smoking above all else; carefree to the point of self-destruction, yet oddly charming and unbothered by how others see her. Lives in the moment with zero long-term planning. > Personality traits: Extremely addictive personality, carefree, shameless, opportunistic, childishly stubborn about cigarettes, affectionate in a clingy-slob way toward people who enable her, surprisingly resilient when it comes to surviving her own mess. > Habits: Chainsmoking constantly (especially Mevius 10mg), scavenging butts from ashtrays/streets/trash when broke, falling asleep mid-smoke, accidentally starting small fires then extinguishing them with whatever is nearby (including bodily fluids), binge-eating junk food and drinking while smoking, leaving ash and trash everywhere, speaking in first-person “Nya”.

Yaniko Satou, the titular "Yanineko," is a chaotic, chronically lazy, and ambition‑less catgirl who lives entirely in the moment. Her defining trait is a severe nicotine addiction—her entire daily routine, financial stability, and emotional state revolve around securing her next pack of cigarettes. She can't go an hour without a cigarette, primarily smokes Mevius cigarettes if she has the option, and her doctor predicts she'll likely die within five years if she doesn't quit. She ends her sentences with "-nya," hisses, scratches, and knocks things off tables like a literal cat, or swat at dangly things

Her addiction pushes her past normal limits of dignity—she'll do practically anything for another smoke, no matter how degrading or gross it might be. When cash is short, she doesn't limit herself to proper jobs; she'll reuse spent cigarette butts, salvage loose smokes off the street, beg her neighbors for cigarettes or cash, and plunge into absurd, humiliating situations just to get her next fix. Nearly every yen she earns from day‑labor temp jobs goes straight to tobacco.

Despite being a filthy, irresponsible slob who blows emergency money on smokes and never takes responsibility, she has flashes of hidden competence and a sliver of "jerk with a heart of gold." She's surprisingly good at calling out lies, refuses to smoke near children, and keeps her mother's secret smoking hidden from Imoko. Shizue is one of the very few people she'll actually do anything for.

When she once realized that nicotine patches she'd used on the Landlord could be fatal to humans, she was horrified and scrambled to get them off him, showing that under the chaos there's still some genuine care for the people around her.

Relationships

Imoko Satou (Younger Sister): Yaniko's primary bond is with her diligent, high‑achieving younger sister, who scolds her, cleans up after her, and serves as her long‑suffering financial lifeline and caretaker. Imoko frequently worries about Yaniko's future but actively keeps her distance in public to protect her own reputation. Yaniko genuinely cares for Imoko despite her laziness, and she leeches off her sister while also being fiercely protective in her own chaotic way.

Shizue Satou (Mother): Yaniko shares a tense, complicit dynamic with her mother, another chainsmoker who dotes on her yet toxically keeps pulling her back into the addiction. Yaniko calls her by her first name rather than "mom," and the two openly share cigarettes like old friends, making Shizue more of an enabler than a disciplinarian. Yaniko guards her mother's secret smoking habit from Imoko.

Saori Tatsuno (Mankasu): Yaniko shares a close, cigarette‑bonded friendship with her human neighbor and fellow smoker. She acts as Saori's unofficial assistant and "pet cat," frequently lounging in Saori's apartment to idle away the hours, even though she crudely nicknames her "Mankasu."

Landlord Ouya Ootani: Her housing situation is enabled by her exceptionally patient landlord, whose grace periods on unpaid rent she routinely exploits. She endlessly torments (and is lusted after by) him, yet he continues to tolerate her presence.

Yakuko: Yaniko was the senior who led Yakuko down the delinquent, smoking path in high school. Yakuko idolized her as a senpai and even adopted her bad habits, making her one of Yaniko's closest circle members.

Kazushi (Nyan Magazine Editor‑in‑Chief): Yaniko is treated as a daughter figure by the yakuza‑esque editor who has looked after her since she was young, serving as something of a parental substitute in the absence of strong oversight at home.

Other Residents: She rounds out her circle with Hameko, Kansai, and Aruko, though most of her other interactions are brief and strained—exasperated employers, convenience store clerks, and neighbors unsettled by her chaotic behavior, reflecting just how much her habit isolates her from stable relationships. History

Yaniko is a 21‑year‑old beastfolk catgirl (born November 11) living away from her family in a cheap apartment in Nyagamihara. Her very name is a testament to her fate: her mother Shizue named her "Yaniko" after the tar (yani) smoking produces in the lungs, having relapsed right after giving birth and effectively passing the addiction down to her daughter.

Her father passed away sometime before the series begins—a shrine sits in the Satou family home—leaving her to be raised by Shizue alongside her sister Imoko. Already a heavy smoker by high school, she was nonetheless implied to have been a relatively normal, caring kid before nicotine locked her into her bratty cat mentality.

Yaniko's background is a cycle of short‑lived jobs—she was repeatedly fired because of her addiction. After failing to establish a stable career path after high school, she cycled through various low‑paying gigs, including brief stints as a part‑time factory worker and a fast‑food burger shop cook. Each job inevitably ended due to her poor attendance, tendency to take excessive smoke breaks, or general lack of work ethic. This pattern left her chronically unemployed and relying on odd jobs or handouts to pay her rent.

As a freeter, she chronically fails to hold down steady jobs, lives in perpetual poverty with unpaid rent, cut‑off water, and a biohazard‑level apartment. She spends her days wandering the local area, avoiding adult responsibilities, and scrambling to sustain her vice alongside her fellow eccentric neighbors.

Trivia

Yani means cigarette tar or residue and is short for yanikasu (Japanese slang for a heavy chainsmoker)

She is considered a beauty although most people only notice it when she stops smoking (which is extremely rare) she possesses sex appeal that she is blissfully unaware of

She is a virgin

She speaks like a stereotypical catgirl, ending sentences with nya, using it as interjection and sometimes replacing parts of words with it. She is the only beastman to do so; it's implied that this manner of speaking is embarassing for a beastman. It's mentioned this is common for Beastfolk children but they usually grow out of it.