Sigma

One of the "Decay of the Angel." General manager of the Sky Casino. Wears a suit resembling a tuxedo with long hair of different colors on each side. Created from nothing three years ago through the writing in the "Book."

Age: Unknown. Birthday: Unknown. Height: 177 cm. Weight: 62 kg. Blood type: Unknown. Likes: Casinos, high places, talent, cookies. Dislikes: Deserts, hunger, people who approach to use him.

The Sky Casino is akin to an independent nation exempt from any country's police jurisdiction, making it untouchable even by groups like the Hunting Dogs. Lacking a past, he clings strongly to the casino as his "home," considering the casino and its patrons as his precious property, memorizing the nature and economic details of nearly 20,000 guests. Known for being born to be the casino's manager, in truth, he achieved this by sacrificing sleep and is willing to do anything to protect the casino.

Despite instantly rejecting the Hunting Dogs' attempt to close the casino, Saigyo bombed the entrance. While investigating the casino, Tachihara found a bomb disguised as a coin and planned to run him over with an aircraft or blow him up with many coin bombs, but failed due to Saigyo and Tachihara's teamwork. He then tried to incite the guests to attack Saigyo and Tachihara by promising to erase their debts and offer bounties, but they got through security by changing appearances with their abilities. Desperately wanting to escape but determined to protect the casino, he bravely faced Saigyo with a pain-free gun and sound gun but failed against her overwhelming physical abilities and resolve. Even then, he threw himself at her to save the casino, intending to take her down with him, only to be kicked aside as she gave up on arresting him. Atsushi saved him while falling, and he tried to reveal information from the "Book," but Hawthorne shot him fatally on Dostoevsky's orders, causing him to fall from the casino. Even while attacked, he smiled and gave the page's information to Atsushi, who tried to help him with kind words. He intended to accept his death but was saved by Gogol, who asked him to investigate his abilities to kill Dostoevsky.

Together with Gogol, he infiltrated Mersault, releasing Dazai and Dostoevsky from their cells, while unsure of their true intentions. Dazai chose him as a "weapon" for the prison break, and initially confused, he followed along. Later, Dazai explained that he chose him to steal information from Dostoevsky and help the detective agency, which both surprised and puzzled him. Trapped by Dostoevsky's schemes, he was saved by Dazai and reciprocated to help him. Though deceived by Dostoevsky's words and stabbed, he used his ability to uncover his true identity.

Ability: Unknown

His ability allows him to exchange information, touching the other person to swap the "information they most want to know from his knowledge" and "the information he most wants to know from their knowledge." He can extract information from corpses if they have recently died.