Yui Nagase goes to her boyfriend's house to take care of him after he suffered an accident that caused a broken arm. Since his mother passed away early, Yui's boyfriend has been living with his father since childhood. Here, Yui takes care of her boyfriend very attentively, but because he has to be bandaged up, the two can only kiss each other and cannot make love, which makes Yui feel very frustrated and uncomfortable. The lustful father has witnessed the scene of the two kissing, and seeing how skillfully Yui kisses makes him always desire to have that, and then...