@Lan Anh Nguyen Sejin lives internally. He thinks and processes and considers but rarely does any of that get spoken out loud or shared with anyone. It's his greatest flaw. In all the timelines. I don't think he's selfish so much as self centered (if that makes sense) due to how he was abandoned and raised by his adoptive family. Survival meant silence, obedience and minimizing. The only reliable person was himself. But by the third life and seeing how everything went wrong why can't he say something? It's driving me crazy. He must understand that his silence and obedience contributed to past misunderstandings and robbed him of an opportunity for happiness and freedom from his shi*** family. I'm not one for shouting about communication but Sejin surely needs to learn to use his words properly. His internal dialog is wise and caring but his ability to speak remains stunted and weak.