Was it really just a normal day in the park? No. Byun Baekhyun was rushed immediately to the hospital, passed out. 

Park Chanyeol shouldn't feel bad, he didn't do anything wrong. All he did was dare his best friend to jump of a swing. He didn't do anything bad did he? But Chanyeol thinks he did something bad. Real bad, because his only best friend is now in a deep coma, where he peacefully asleep lies in the white hospital bed. People call Chanyeol a mean, heartless person, and Chanyeol agrees. They are correct.

Three years past and Byun Baekhyun slowly opens his eyes in pain, not remembering a single thing about life.