Seo Yoon Seul’s life has been perfect so far with a dream job and lucky life. Until one day, he started dreaming about the moment he ruthlessly rejected Kang Joon when they were in high school, the unfortunate things are continuously happening to him. Everything is even getting worse when he meets Kang Joon again. Following his friend’s advice, Yoon Seul approaches Kang Joon to gain his favor to become a nice person in order to prevent nightmares.