Bully Hideo's favorite older sister. Yui Hatano

The movie revolves around the complex and intimate relationship between a big sister and her younger brother, exploring themes of innocence, curiosity, and forbidden desires. As they navigate their feelings and boundaries, they must confront the consequences of their actions and the secrets they keep. The story delves into the emotional and psychological dynamics of their bond, blurring the lines between familial love and romantic attraction.