While playing in an abandoned warehouse, step-brothers Asuka and Yui get trapped inside an old locker. What happens inside changes their relationship forever. Yui suddenly starts avoiding his older brother, even going so far as heading to America to study away from him. Years later, after Asuka has begun working in an advertising agency and Yui is still playing tennis in high school, the brothers are reunited and the truth about that summer is revealed.
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Brother (Ougi Yuzuha)