Amu-chan is staying at her brother's place. She adores her brother and doesn't want him to find out about her frequent urination and inability to control her arousal. So she confides in her brother's wife, Chiharu-san. The kind-hearted Chiharu-san, after much deliberation, proposes a plan involving purchasing a large supply of diapers and wearing them during her stay. Chiharu-san, being incredibly earnest (and a bit naive), diligently carries out this diaper plan. This is a heartwarming and romantic diaper drama.