Shiawase ni Natte Mimasen ka?

Kazuhiro proposes to his three-year girlfriend, only to be dumped the same night. He drinks heavily to cope and wakes up in a love hotel with an unfamiliar man, later identified as a coworker, and discovers his engagement ring is missing. He attempts to retrieve it, but the man refuses to return it and expresses interest in continuing their connection. Kazuhiro must decide how far he is willing to go to reclaim the ring, while questioning whether it truly belongs on his finger.