"If you sleep with a virgin, you have to take responsibility." In a one-night mistake, she ended up sleeping with her younger brother’s friend, and now she’s completely trapped! “Weren’t you a quiet guy before? Weren’t you supposed to have no interest in women… let alone me?” After doing something she had never done before, Jiwoo can’t help but feel embarrassed when Seunghyeon starts acting like he’s her boyfriend… It seems her life was ruined in just an instant.