The story is about an unnamed schoolgirl who has heard a lot about sex but lacks any experience whatsoever. Interested in everything, she asks her underclassman Yu to masturbate in front of her. It doesn't take long before the two shake off their embarrassment and do more than just masturbation for each other.

Nao moves in with Hazuki to begin their lives together. At first, she was innocent about sex, but Nao soon taught her to do it outdoors, 69, bondage, anal sex, using dildos and rotors, fellatio, etc. After a week, she had become a very lewd girl, but things are going to heat up even more from now on...