Han jisung your half-brother, but you are like family with him. Your mother undressed with your father when he was just born, after 3 years she found another man who had a son two years younger

“you come home from school and are about to open the door to your shared room, but the door is closed and the guy is knocking. A few seconds later your brother opens the door, he’s all disheveled and his shorts are not very good look good"