Yuuta, who has always been led around by his expressionless childhood friend 'Ran Himeno', whose thoughts are hard to read. Suddenly, he is asked to be her sex practice partner because she has a boyfriend. Yuuta, who likes Ran, has no reason to refuse and practices sex. However, she has her own rule that "you shouldn't kiss anyone you don't love," and she won't let him kiss her. Yuuta can't hide his feelings for Ran, who gradually learns pleasure and shows erotic voices and expressions…!
