While working as a low-ranking helper at a hot spring resort, Ryuuji finds himself caught in a passionate tug-of-war between Sandy and Wendy. After a romantic encounter with Sandy is interrupted by a jealous Wendy, Ryuuji awakens with sudden amnesia, forgetting his relationship with both women. Seizing the opportunity, Sandy and Wendy compete to seduce the confused Ryuuji and convince him that they are his girlfriends.