Ong Seongwoo is a big How I Met Your Mother fan, and lives by the laws Barney Stinson made. That's why when he met Daniel on a blind date, he decides to lemon law him. He looked like a loser laughing for no reason, and Seongwoo knew that this date is going downhill.

After a year and a half, Ong Seongwoo finds himself stuck with Kang Daniel, a red string stopping them from staying more than one meter away from each other.