Chisato is in love with shoma and so is her twin sister, Kuu. Kuu voyeuristically watches Shoma and Chisato having sex in the hot tub. She becomes wet, gets jealous and storms out of the house determined to make it on her own. Fantasy becomes reality when an ex lover of Shoma reappears and she pulls Chisato into their den of sexual debaucher. This three-way love affair will complicate things. What will Kuu and Chisato decide to do?