Rika-chan's mother remarried and she went to live with her uncle Sugiura. She has big breasts that are out of proportion to her still innocent face, and healthy, young skin that is tanned. She presses her huge breasts against him defenselessly and clings to him, so even though he is his stepdaughter, there is no way he can resist his desires. They take a bath together, wash each other's bodies, teach each other sexual knowledge, and lick the uncle's penis. When her pussy starts to itch, the uncle teaches her about sex, and then has creampie sex with the sweaty, tanned, busty girl.