Sigma himself was a person born from being written into the Book. When he first opened his eyes and became aware of his surroundings, the first thing that greeted him was not a midwife or a mother but a vast desert filled with nothingness, and his only possession were the clothes on his back and a train ticket from a station that does not exist. At one point, Sigma was approached and invited by Fyodor to join the Decay of the Angel. Upon agreeing, he was eventually given the duty of overseeing t