The house they moved to has few rooms, so the older sister and younger brother end up sharing a room. As they spend time together in the same space, the younger brother is seduced by his sister's defenseless and seductive appearance. Finally unable to resist, the younger brother attacks his sister as his desire dictates! And the violated older sister also becomes addicted to the pleasure of incestuous sex... A forbidden sex story between a sister and a brother who are connected in Kokoro and body.