Fyodor Dostoyevsky stands as a central antagonist, possessing a tall, slim frame, pale skin, and long, disheveled purplish-black hair falling to his shoulders. Sharp dark purple eyes lend him a perpetually tired look. His signature attire includes a white buttoned shirt with light purple accents, white pants, a long black coat featuring a fur-lined collar, maroon knee-high boots, and a distinctive white ushanka hat. During imprisonment, he appears in standard white prison garb without his characteristic accessories. His personality blends calculated calm, unwavering confidence, and profound enigma. He maintains exceptional composure even in life-threatening situations, rarely revealing fear or agitation. Demonstrating a masterful grasp of human psychology, he wields exceptional intellect, strategic foresight, and psychological manipulation to orchestrate events and control others. Viewing himself as an instrument of divine will, he frequently speaks of humanity's inherent sinfulness and his mission to achieve salvation through purification. This drives his stated desire to eliminate all ability users globally using the reality-altering artifact "The Book," believing their powers represent crimes requiring punishment. He expresses ideals like "blessings for children" and "peace be to all the world" while orchestrating terrorism and mass violence, a stark contradiction noted by adversaries who label him a "Demon." He treats subordinates and allies as expendable instruments, demonstrating no loyalty. He readily exploits their personal desires and vulnerabilities before discarding or eliminating them once their utility ends, exemplified by manipulating Nathaniel Hawthorne's wish to save Margaret Mitchell through brainwashing and memory erasure, and abruptly ordering Sigma's assassination after the Sky Casino operation. He views genuine trust as impossible, associating only with those he can control, resulting in an absence of authentic friendships. His actions, including psychologically manipulating a child into suicide to demoralize Kunikida and using innocent civilians as decoys, underscore his profound disregard for individual lives in pursuit of his objective. His ability, Crime and Punishment (罪と罰, Tsumi to Batsu), initially appears to cause instant death through physical contact, even through barriers like gloves. Its full mechanism is post-mortem body possession. The ability activates when someone kills Fyodor, punishing the perpetrator by transferring Fyodor's consciousness into their body, making them "the next Fyodor Dostoyevsky." This occurred historically when Bram Stoker's executioner killed him, allowing Fyodor to seize that man's body. It functioned again after his apparent death at Meursault prison; the vampire that killed him was controlled by Bram Stoker, resulting in Fyodor taking over Bram's body. The ability remained loyal during the Yokohama fog incident, identifying itself as the necessary "punishment" for Fyodor's "crime." Using this ability seemingly grants Fyodor an exceptionally long lifespan, as glimpsing his life history through information-reading abilities can overwhelm others. Beyond his supernatural power, Fyodor possesses genius-level intellect rivaling or exceeding other strategic masterminds. He demonstrates a photographic memory, evidenced by memorizing minute card details during a game with Ace and creating a complex communication code with Dazai based on recalled past conversations. He is a master tactician capable of predicting enemy actions years in advance and embedding himself within his enemies' plans. His most formidable skill lies in manipulation, exploiting human desires and flaws to turn allies against each other and orchestrate large-scale conflicts, such as instigating the Guild-Mafia conflict and framing the Armed Detective Agency. Significant background details involve his leadership of the criminal organization "The Rats in the House of the Dead" and his founding role in the terrorist group "Decay of the Angel." His earliest known act involved being captured and executed by Bram Stoker's men centuries ago, only to seize his executioner's body via his ability. At an unspecified point, he fabricated a prophecy about a future world war to manipulate Ōchi Fukuchi into establishing the Decay of the Angel and initiating a global terrorism plot, positioning Fukuchi as a figurehead while secretly controlling events. He met Osamu Dazai at least once prior to the main storyline. Three years before current events, he encountered the newly born Sigma and offered him a place to belong, recruiting him for the Sky Casino operation. He also temporarily allied with the Guild and the Order of the Clock Tower in pursuit of The Book. Fyodor's significant plot involvements include attempting to crash the Guild's airship Moby Dick onto Yokohama to eliminate ability users, collaborating with Shibusawa in the Dead Apple incident partly for entertainment and to observe ability users succumb to their powers, orchestrating the Cannibalism arc by using a virus ability to force conflict between the Armed Detective Agency and Port Mafia, masterminding the framing of the Armed Detective Agency for terrorism via the Decay of the Angel and the page from The Book, and infiltrating Meursault prison as part of a larger scheme. His plans culminated in manipulating Fukuchi into triggering a global vampire pandemic using Bram Stoker's power. After his physical body was killed during the prison escape attempt, he utilized Crime and Punishment to possess Bram Stoker's body. Philosophically, Fyodor perceives humanity as fundamentally sinful and foolish, inherently drawn to violence and self-destruction even when aware of manipulation. He views death as salvation, releasing individuals from sin and suffering. His stated goal is world peace, achieved by eradicating ability users and establishing a new world order "atop the corpses of ability users," believing their existence disrupts divine harmony. He justifies his brutal actions as necessary for humanity's ultimate purification and deliverance. Symbolic elements include recurring motifs of hands and arms, representing divine guidance, judgment, power, and vulnerability. His open gestures can signify deceptive honesty and a willingness to embrace outcomes. Quotes like "People can be so simple. They truly believe they are thinking for themselves" reflect his cynical view of human independence and reliance on manipulation through perceived self-discovery. Trivia notes include his self-described strengths ("a heart to wish world peace") and weaknesses ("low blood pressure"), his stated desire for "a talkative person with the same level of intelligence," habits like praying before sleep and listening to classical music as a reward, his comparison of himself to "the white of my hometown's snow," and his expressed desire to be "the essence of everything" if reincarnated.