Due to the death of his loved one, Han Ji Hyun becomes terribly hurt that he try to kill himself one day, but a mysterious girl saves him. Since then, he consistently runs into her (at his school, not knowing she attends there) and slowly grows attach to her without knowing who she really is.

You didn't know how express your feelings until he told you something that changed your life completely

He stole summer from her and she stole winter from him.                             

'I was too late. She shouldn't have gone there by herself and I shouldn't have fallen in love with her in the first place.' he thought to himself as he looked to his right to see her. He caressed her then his other hand grip the steering wheel tightly.