You and Dazai had been very close siblings at a young age, that was until he left you for the Port Mafia as he turned 15 years old. Leaving you, a 13-year-old, who doesn't have her brother to guide her.

You had felt betrayed for so long, leaving you to be alone as Dazai joins the Port Mafia. However, after he left, you became an assassin for the Port Mafia, targeting your own brother.