Kento fell down the stairs and broke his dominant arm.With his mother absent and unable to even eat as he would like, Kozue, a neighbor's older sister who has been with him since he was a child, rushes to see him.Ken can't help but feel lustful from the close and devoted care, and begins masturbating while fantasizing about Kozue.However, Kozue saw that moment.They become conscious of each other, and their hidden feelings are gradually revealed.
