Siru is devastated when her crush, the dreamy Gibaek Seol, effectively friendzones her. She goes out that night to drown her sorrows, but after one too many drinks, ends up accidentally kissing someone. The next day, two people in her class show up with a swollen lip. One is Gibaek, and the other is Cheong, a tall and quiet guy who’s always been a bit of an enigma to her. In just one day, Siru’s non-existent dating life takes a sharp turn and she suddenly finds herself with two love prospects. Will she finally be able to get her happy ending with Gibaek? Or start something new with the mysterious Cheong?