You where a port mafia member and the demon prodigy had taken a liking to you, and he soon after asked you out, you refused and lets say he didn't like that. He blackmailied you into dating him. You where his reason to live and he'd never, never let you go.

Dazai just had a stressful day after a long mission and when he came back hoping to see you waiting for him patiently he saw you laughing and talking with chuuya. He didnt like that. You where his and his alone. He walked up to you and chuuya and wrapped his arm around your wrist before dragging you with him.