Fyodor Dostoevsky/Synopsis

The Guild Arc
Fyodor is first seen when discussing the operation with Fitzgerald and Agatha, mentioning that he has foreseen the events that took place earlier.

It is unknown what he was doing during the war. Nevertheless, when Atsushi Nakajima and Ryunosuke Akutagawa were battling against Francis Scott Key Fitzgerald, Fyodor accessed Moby Dick's controls and forced the warship into a free-fall after the latter's defeat. Sometime later, after taking a quarter of the Guild's funds, he encountered Nathaniel Hawthorne and together they made a deal to help each other as long as Margaret Mitchell gets proper treatment. Agreeing to his condition, Fyodor states that his next step is to cleanse Yokohama of the sinners.

The Guild Aftermath Arc
Spreading disinformation about the leftover Guild's fortune, his plan is set in motion in order to lure criminal organizations and bring a wave of crime. Osamu Dazai states this truth, while a focused Fyodor is somewhere at the bay staring at the sea.

Later, during the events after the Guild War, he lets himself be captured by the Mafia, specifically by a man named Ace, one of the five executives of the Port Mafia. While the executives and the leader were discussing his fate, he was waiting in an underground prison.

Ace shows himself to him, stating his name. Fyodor then is set free and brought to talk to the man about joining forces together to destroy the Mafia. Nevertheless, he promptly denies and then threatens the executive to kill him, which angers the executive and is then hit by a bottle of wine. The man leaves, leaving only Fyodor together with a young boy named Karma, who dries him up and they have a small conversation. After Ace returns, he is surprised to see the Fyodor eager to play a game of High or Low, which he wins flawlessly. Angered by this, A orders his subordinates to come, but then is taken aback by the fact that nothing appears to be working, and is then deluded by Fyodor into thinking that it is the work of his ability.

Ace is tricked into committing suicide after coming to the conclusion that it is the only way to escape Dostovesky's supposed ability (the ability to lock others in your consciousness), where in actual fact, Fyodor had set up the room around them in order for it to seem like a false reality. He leaves Ace's body and escapes the room where he encounters the young boy he conversed with earlier who is shocked by the fact that Fyodor beat Ace. It is revealed that Fyodor purposefully leaked information of his false ability and a way to escape the false ability to the kidnapper in order to trick Ace. He proceeds to reveal his true motive, gaining a list of the Port Mafia members and their abilities, which Ace compiled as a part of his plot to take over the Mafia. Stating that the list's value will be halved if the Mafia were to know that he owned it, Fyodor states that he must not leave any witnesses. He uses his ability to instantaneously kill the young boy and calls himself as a God while leaving the burning cruiser and stating his next objectives: the annihilation of the Port Mafia and then, the Detective Agency.

Cannibalism Arc
Following the attack of Fukuzawa by a masked assassin (later revealed to be Hawthorne), Fyodor disguises himself as a policeman. After the car that Mori and Elise plan to drive off in explodes, policeman Fyodor comes to "investigate". He asks an unsuspecting Mori about the cause of the explosion and when answered, asks Mori if he is okay. Fyodor then proceeds to stab Mori. While Mori is falling, he knocks off Fyodor's police hat to reveal his true identity. Fyodor runs away and Elise loses sight of him because of the large crowd of bystanders.

Fyodor runs into an alley and sheds his police disguise, changing into his usual clothing. He searches a compartment in the alley where he placed his Ushanka-hat only to find that it isn't there. Dazai appears and Fyodor instantly recognizes him. Dazai, having figured out his plan, states that it is just like Fyodor to tamper with the mind of Hawthorne and turn him into an assassin. Dazai reveals that Fyodor's aim is to obtain the mysterious Book, but first, he has to exterminate Yokohama's ability users. Since the 'Rats' don't have the firepower to burn down the town like the Guild, Fyodor took out the heads of the Agency and Mafia through assassination. Fyodor asks Dazai how he came to such a conclusion and Dazai says that it's 'because it's what I'd do'. Fyodor smiles and asks Dazai if he's suggesting that they're alike.

Fyodor tells Dazai that the poison given to Fukuzawa and Mori 'assures mutual destruction'. He says that he won't destroy the two organizations- they'll do it themselves. He explains that the poison is from a virus-type ability held by a certain criminal friend of his. Over 48 hours, their bodies' microfauna grows and eats away at the internal organs of both hosts. However, if either host dies before the 48 hours ends, the ability will stop.

Fyodor states that people are 'sinfully stupid' and despite knowing they're being manipulated, they will continue to kill each other, nevertheless. He says that someone must rid them of their sins. Suddenly, a sniper shoots Dazai and he realizes that Fyodor predicted his actions. Fyodor tells Dazai that his vitals weren't hit because he still has a part to play in his plan. Then, Fyodor realizes Dazai knew the sniper was there. Dazai says that 'The Book' is a single book of blank pages where anything written in it becomes the truth. Fyodor says that he will use the book to rid the world of the sin of ability users. Dazai challenges Fyodor to make that happen. Then, they hear Kunikida and Atsushi searching in the alleyway for Dazai. Fyodor leaves the scene.

Fyodor appears where he is seen playing the cello. It is revealed that he gave a bunch of weapons to a man called Pushkin and his family. Pushkin then passes a message by Fyodor to the Agency, "the rules cannot be changed."

Fyodor is seen drinking coffee in a cafe when he is approached unexpectedly by Dazai and Fitzgerald. It then dawns on Fyodor that they used the Eyes of God to track down his location. Fitzgerald reveals that he couldn't stand Fyodor keeping the money he stole from him that he decided to add the Armed Detective Agency in his capture. Ango then appears with some armed men to take Fyodor in custody. Fyodor decided not to put up with a fight and goes willingly with Ango.

Decay of Angels Arc
Fyodor is seen chained by the neck in an unknown area.