"Want to touch your nipples?" Stepmother Manami makes an unexpected suggestion, and brothers Kenta and Akihiro timidly reach out their hands. They open their eyes wide at the sensation of their new nipples, but gradually become fascinated. Seeing this, Manami breathes a sigh of relief. Since her remarriage, Manami has been fed up with the awkward relationship with her stepson, and hopes that this physical contact will help them become closer as a family, but... beyond Manami's expectations, the brothers have become obsessed with her nipples...