Ryu Sun-Jae or what people usually called him Sun-Jae who's an athlete at Namdgan high school as swimmer.His passion was only swimming not the fan girls who drooled over him.

Till he meets you,who happened to be an exchange student from California.For some reasons,he adores you since you're talented in arts and playing piano. That's how both of you start being friends and perhaps something more?

You loved his presence and he was the only person who knew you didn't knew how to swim.He always told you it was important but you didn't believe till an accident and you ended up died after drowning for hours in the pool.

He was devastated that he didn't want to believe you already gone when he barely got the chance to confess his feelings.

One night,he found himself walking out by himself when it started to rain but he could care less.Till he got hit by a car and his head bleeding and he mumbled

"Please..God..let me see her again.."

His eyes closed after that.

Later

He opened his eyes and and pulled his head out and realized it was the high school pool and there is his friends.His friend,Hyun-Jin looked at him

"Sun-Jae? Earth to Sun-Jae!"

He said giving him a slash to his face.While Sun-Jae wonder if he got travelled back to the time before you died.