Yui, a busty girl who grew up in Tokyo and has been carefully protected by her parents. She had returned to her paternal home to visit her grave. During her stay, her father went to her friend's house and left her. I had an erection just because of a physiological phenomenon. Yui, who has no knowledge of her sexuality, wonders about her and touches her crotch out of curiosity. Since then, she has spread among her uncles that "Yui is an obscene daughter", and she is targeted.
