Fyodor Dostoyevsky

Fyodor is a tall and slim young man with long, dark, and messy hair that reaches his shoulders. His eyes are sharp and of a dark purple color, giving him a tired look. He wears what appears to be a buttoned white shirt and white pants; accompanied by a long black coat with white fur, and an ushanka hat. He also wears red long boots.

Showing a calm and confident personality most of the time, Fyodor doesn't appear to fear to his enemies, boasting enough courage to let himself be captured by them. Despite being extremely arrogant, he is a straightforward and intelligent man with a truly sinister personality.

He refers to himself as carrying out the lord’s will and always talks about the sinful nature of man. Ironically, Dazai names him "Demon", saying he had met Fyodor only once in the past.

In the past, Fyodor was mentioned to have been met Osamu Dazai at an unknown point in time. Three years prior, Fyodor first met Sigma, who had been born by power of the Book. The Russian asked him if he wished for a home, an offer that Sigma accepted.

Later, Fyodor apparently allied himself with the Guild in an attempt to acquire the Book, presumably together with the Order of the Clock Tower.