Prison School volume 6 features story and art by Akira Hiramoto.

An unthinkable "nightmare scenario" is brought down on the Shadow Student Council, shaking the Prison to its core! Kiyoshi falls into the trap laid by Kate, the Regular Student Council President, and finds himself behind bars once again! Now Mari, Meiko, and Kiyoshi must share a co-ed Prison. Meanwhile, Kate's plan for revenge is quietly set into motion!