I think he was kidnapped…
It didn't really explain in the manwha tbh so ask the novel readers
He left on his own, because when he stays beside Taeui, his luck's at its strongest. He want to experience his life less lucky as possible. Then he's invited to live at Ramah's house
Wasn’t it because his uncle was pressuring him to keep on doing weapons while he didn’t want to? And all those organizations were looking for him?
From what I remember, he doesn't want to make weapons anymore because Taeui says weapons are scary or hurtful, so he just quits.
Can someone tell me why the brother disappeared in thr first place and left everyone without a word. Did he want to or was he forced? Many many questions...