Kuzunosuke Beri

Beri is authoritarian, manipulative and entertained by the suffering of people under his control. Rather than treating imprisonment as punishment administered according to law, he exploits the inmates' rivalries and vulnerabilities for his own amusement.

He is particularly comfortable creating situations in which prisoners turn against one another. The apparent security of his position encourages him to behave as though consequences cannot reach him.

Beri's conduct contrasts with Sakata Gintoki's unexpected concern for the prisoners. Gintoki may initially treat incarceration as another absurd inconvenience, but Beri's deliberate humiliation of vulnerable inmates gives him a reason to take the prison's internal problems seriously.

Beri has no supernatural abilities. His power comes from his position as prison warden, which gives him authority over guards, inmates and the conditions under which prisoners live.

He understands how to manipulate the prison population and uses institutional control to pressure inmates against one another. This makes him dangerous without requiring the exceptional physical strength common among Gintama's major combatants.

When the prison's internal order collapses, however, his formal authority proves much less useful against the consequences of the resentment he has created.

The Yorozuya are initially hired to collect money from a customer at a peculiar establishment. Because the debtor is associated with a prison-guard uniform, their investigation results in Gintoki being mistaken for the offender and taken into custody.

Inside prison, Gintoki encounters Shachi and an elderly inmate. Beri presides over the institution and exploits the divisions among its prisoners, eventually helping create conditions that lead to a riot.

Gintoki becomes increasingly involved in the inmates' lives rather than simply looking for a way to escape. Beri ultimately accepts responsibility for the riot and attempts to atone through seppuku, but Gintoki prevents the matter from ending so simply and forces him to help fulfill a promise to the elderly prisoner.

Sakata Gintoki becomes Beri's prisoner after a misunderstanding. Gintoki eventually opposes the warden's manipulation of the inmates and forces him to confront the consequences of his behavior.

Shachi is one of the prominent prisoners living under Beri's authority and becomes involved with Sakata Gintoki during the prison conflict.

Gramps is another prisoner subjected to the environment Beri controls. His desire to communicate with his estranged son becomes an important part of Sakata Gintoki's involvement in the prison.