From Stiletto Heels:

Momoko, who dreams of becoming an illustrator, finds employment in an ultra fast-paced office that specializes in designing pachinko parlors!! With the office running a yakuza-like business and employing a designer who has a habit of suddenly stripping in the middle of the night, Momoko believes that the company employees are a bit... no, definitely eccentric!! She continues pulling all-nighters, unable even to return home... And in the midst of that cigarette smoke-filled office, where women's authority takes a step back, she asks herself, "Why am I here?"