Kenichi

25-year-old factory senior coworker with glasses; married to Fumina; lends his wife to junior Namino for sex, watches from outside the room, then joins a threesome including anal and vaginal sex until late night.

Kenichi's married mother. Continues vaginal sex, breast play and creampie with Yota, tries to make him her exclusive sex partner, and keeps having sex while her son sleeps.

21-year-old university student living alone in Satsuki's apartment who admires her. After witnessing her affair he becomes her sex partner the next day, continues creampie sex and daily visits, then invites friends for a gangbang party.

25-year-old wife of Hirata Gaku; large breasts and huge buttocks; appears demure but is a nymphomaniac who performs fellatio, vaginal sex, creampie and double penetration with junior Namino and her husband, then invites Namino back for partner exchange.

33yo black-company salaryman of about 10 years, body and mind exhausted, and a virgin. Dragged into neighbor Sora's drinking party with Rin and Natsuki, exposed as a virgin, stripped after breast exposure, receives fellatio and facial from Natsuki, has first intercourse with virgin Rin nearly creampieing before using a condom, then doggy-style sex with Sora, continuing overnight group sex with all three 20-year-olds and still having sex with them the next day while job-hunting.

20yo clothing-store worker, blonde with large breasts. Newly moved next door, throws loud drinking parties, wakes Bunzo, apologizes and drags him to the party. Calls herself the lewdest of the three, spreads her vagina waiting for his penis, takes doggy-style penetration, climaxes forgetting work and seniors, and joins overnight group sex.