Onee-san-tachi to Sex de Shoubu Shiyo?

A young boy finds himself surrounded by older women who challenge him to sexual contests. Each chapter presents a different scenario where the protagonist engages in erotic battles of skill and stamina with various female opponents.

From a lewd sketching session to a fight for control of a secret base, the boy must use his wits and endurance to keep up with the experienced women. The stakes are high as he tries to prove himself in these intimate competitions.