Puri-Puri Prisoner vs. Prisoners of Smelly Lid Prison

Puri-Puri-Prisoner vs. Prisoners of Smelly Lid Prison is the battle among the S-class hero Puri-Puri-Prisoner and the newly recruited members of the Monster Association who were formerly prisoners of the Smelly Lid Prison.

Preview
As Puri-Puri-Prisoner finishes eliminating Vacuuma, the prisoners of Smelly Lid Prison comments on that he's a monster among monsters and that they can no longer think of him as human. They remember all of the time they tried to cut his head off while he was sleeping, but his skin was so tough that no razor blades could pierce it. The monsters eagerly prepare their revenge and declare the hero as their sworn enemy. Puri-Puri-Prisoner recognizes those voices and is shocked that the prisoners were captured and transformed them into monsters. He also is sickened that they monsterfied such weak men, enraging the monsters for calling them weak and causing them to charge the hero. As they all blitz Puri-Puri-Prisoner, each of them speaks and talks about the punishment they endured in their prison. One of them says they will go back to the prison and kill the guards, while another says that the Deep Sea Kiss punishment was absolutely unforgivable, adding onto this by saying they would've been legendary serial killers if it wasn't for him.

Puri-Puri-Prisoner is saddened that the prisoners had their hearts corrupted after becoming monsters, although the prisoners assure him that they've always hated his guts. Puri-Puri-Prisoner is shocked by this, and tells them to remember all of the memories they made together. Unfortunately, the prisoners are not moved, causing Puri-Puri-Prisoner to tear up, as he still loves the prisoners and is determined to save them. Then, out of nowhere, a monster appears from behind Puri-Puri-Prisoner and tells him that once someone becomes a monster, they can never go back. This monster is revealed to be Nyan, and before Puri-Puri-Prisoner can even react, Nyan slashes the hero across his chest with minimal effort, yawning in the process. He attacks the hero again with his Feline Retribution, drawing up large portions of blood and ripping Puri-Puri-Prisoner's sweater apart.