Satoshi, a university student who has the worst exam scores and is in danger of advancing to the next grade due to his habit of slacking off on a daily basis. Worried about Satoshi, his mother decided to ask his sister, Chieri, who lives in Tokyo, to watch over him. Satoshi is puzzled by the unexpected start of living together with his aunt. It's like a prison life and I can't even masturbate... On top of that, I happened to witness Mochieri's ripe naked body! Satoshi, who is at the age where he wants to fuck, can no longer suppress his sexual desire that has accumulated.