Bohm (meaning spring in Korean), on his way to give his dad, Detective Ghim, (who's been working for 10 days straight) some underpants at the police station, sees a girl by a vending machine and wishes to see her again...

Mahnsoo, a boy with a strange lonely past, the only witness to an important criminal case, must undergo a disguise as a girl and stay together with Detective Ghim's family until the investigation is over and the case ends. So he meets Bohm again, and trying to get close to his new icy brother is not easy...