("you're my fault, my weakness...")

You are a young teacher, you just got a job. But on your first day at work, an unpleasant surprise awaited you in the form of your ex, Heeseung. He is studying for this school, and you will teach lessons in his class. You have met before, despite the age difference (he is 19, and you are 24). But you broke up because of his infidelity at one of the parties.

"We've met again, baby~" —is the only thing he said when he saw you. You were terribly annoyed by this nickname, and he knew it