Summer vacation Ena Satsuki learned the pleasure of anal sex after her anus was toyed with and developed by an abnormal anal uncle.

The movie revolves around Ena Satsuki's summer vacation experience where she learns about anal sex from an older man referred to as 'uncle'. The story explores their unusual relationship and the development of Ena's understanding of pleasure through her interactions with him. As the title suggests, the focus is on Ena's journey into discovering new aspects of intimacy and sexual exploration during her vacation.