On the very first day of her new semester—and the start of living alone—Yeonhee runs into Kim Jun, a thug-like guy who nearly scares her to death after mistakenly thinking she was stalking him. Praying she’ll never see him again, she’s horrified to discover he lives next door… in the same building, attends the same school, and is even in the same club. Constantly stressed by her terrifying neighbor who looks like he might kill her, Yeonhee soon finds herself confused when Kim Jun suddenly starts acting completely differently—and begins approaching her in unexpected ways.