
SPOILERS NEXT FEW CHAPTERS
OK so Siwoon isn't hiding anything bad, he is visiting his estranged grandmother in the hospital. After all the shit happened when he was in high school she wanted nothing to do with him and blamed him for his mother's actions. Now that is what is fucked up, the night they broke up Siwoon went home and his father had snapped attacking him, than he says "you are not my son" and is about to kill Siwoon until his mother bashes the father's head killing him. Than she says goes on how he should have loved her and the eeason why he didn't, was Siwoon. So she takes the lighter and lights the house on fire and leaves an injured Siwoon to die. But he didn't and she gets locked up in an asylum I think and that's why the grandmother rejected him. Doha is waiting for Siwoon and hugs him, and Siwoon breaks down crying. After hearing Doha say he was sad Siwoon kept this from him Siwoon finally tells him everything.