Shouta is very affectionate with his stepsisters Rena and Aina, with whom he grew up as if they were real brothers. Day by day, his displays of affection towards Aina become more daring… to the point of sneaking into her room at night?!
Rena, seeing this situation, stops Shouta, but she ends up being the one who receives those intense displays of affection instead of Aina.
Due to her hidden feelings for Shouta and the pleasures she is experiencing for the first time, the pure and blameless Rena slowly begins to be constantly trained Shouta…
