Warden's office

The warden's office is used by the warden of the detention center and prison for a variety of purposes. This includes storing evidence and interrogating prisoners. The neighboring prison courtyard is blocked off by an electrified fence.

The Supplier
When an assassin named Ryōken Hōinbō was sent to prison, he blackmailed Marī Miwa, the warden at the time, telling her that he had minions and that he knew a secret that would prove devastating to her and Bansai Ichiyanagi, the chair of the Prosecutorial Investigation Committee. One of these resulting favors granted to him involved smuggling various items that he demanded for the sake of the other prisoners. To create a smuggling route, Miwa enlisted a prisoner named Frank Sahwit, giving him her key to the breaker room in the prison courtyard and telling him to cut the power to the prison at a specified time every week. This allowed her to go through the electrified fence undetected and drop the goods down a well for Kuro, Hōinbō's dog, to pick up. Miwa would interrogate the assassin on a regular basis to try to get him to give her more information about his henchmen, to no avail.

Driven over the edge

 * Main article: The Imprisoned Turnabout

The situation reached a breaking point in March 2019, with the arrest of Manosuke Naitō. While intercepting Naitō's mail, she was horrified to find that he was apparently playing chess with Hōinbō through mail correspondence. She wrote to Ichiyanagi on her suspicion that Naitō was in cahoots with Hōinbō, and interrogated him two days after his initial detainment. During the interrogation, Miwa found a portable chessboard in Naitō's possession and opened it to find a small chisel hidden inside. Knowing that Hōinbō had taken up chiseling during his stay in prison, Miwa took this as a sign that Naitō was here for nefarious purposes. In a panic, she took the knife that Hōinbō had used in his assassinations, and stabbed Naitō in the neck, killing him.