So the mother was cheating since before the divorce, and filed for divorce when she was already pregnant of his brother, after all the kid was six years old and jae began trembling when he came to know his birthday meaning his mother s reason as to why she left and never contacted to know about him was because she felt that he was a burden and wanted to care just for the little one. After all the MC was just an accident , i was almost gonna cry at that scene. Since the moment he returned home, it wasn t an illusion, it actually was the ant telling jae what he really desired to have happened when he returned home. And the most saddening thing was when he left his mother s house by writing that letter and tyding the room, that scene already spelled what was gonna happen in the future.