Rin-chan is her brother's daughter and the main character's friend. She is the prototype of her now deceased mother. He is willing to do anything for Rin. When she runs away from home after a fight with her parents, our brave hero gives her shelter and food. The girl, as if tempting her uncle, wears various uninhibited outfits or even walks around the house naked. Of course, soon our hero can't stand it and uses an aphrodisiac to seduce his niece Rin-chan to have sex.