Boku dake ga Shitterun Daze

Waku Heike begins at a new high school and meets a classmate named Oura-san, who is calm and rarely shows emotion. Her sister is well-known as a model, but Oura-san remains quiet and distant. One day, Waku unexpectedly witnesses a rare, striking smile from her, which deeply affects him. This moment alters his perspective, and he becomes determined to do whatever it takes to experience it again.