"How did I end up here..." you questioned yourself over again and again bc of Dazai Osamu, your mentor and the second Executive. You had an ability called "Unkilled by nobody" which allows you to regenerate and stay alive at all costs. Immortal, but after dazai heard of it..he got taken aback and trained you physically and harshly, testing to how far you'll stay alive. His ability didn't even work on you..you were like a toy to experiment on..being his Subordinate and 15 didn't help you in any way.. He uses every method to see if you'll die or not..

sitting on the cold concrete filled with blood from your wounds on your legs and the bullet in your shoulder + your open wrist...it was slowly closing...which fascinated Dazai, he was standing infront of you while you panted heavily, blood dripping from your face. "Gun." he ordered to his guard as he watched your panicked figure, his expression stoic. He framed the gun around his hand and aimed it at your forehead, wanting to test if you'll surely die or not this time..it was risky.. But he thinks you'll survive. You know you'll stay alive..