Chapter 51

"Don't Put It Back!" (戻すな!, Modosu Na!) is the 51st chapter of the One-Punch Man manga series.

Part 1
The Hero Association staff members begin to discuss about the threat that Garou poses and how he recently began attacking staff members. The association agrees to assign heroes to protect its cadres when they are in public. Garou is seen in a shack with a wall of photos of heroes he possibly wants to fight.

The Hero Association begins assigning heroes to their new assignments by calling King, but King declines the request, replying that he is already busy fighting a monster when in reality he is just playing a video game. Afterward, Metal Bat is seen paired with protecting Narinki, a sponsor and his son Waganma at a restaurant. It is revealed that, unlike King, Metal Bat wasn't even given a choice. Waganma begins trying out the different foods at the restaurant, but he constantly puts the dishes back, even when Metal Bat tells him not to. This cycle slowly starts to frustrate Metal Bat until his sister calls. She asks him to help her with her shopping bags, but he declines because of his mission. His sister ends the call crying and Metal Bat makes a remark saying that he should be the one crying.

Part 2
Suddenly a rumbling occurs and Metal Bat rushes back to the sponsor. Junior Centipede and Venus Mantrap emerge from the ground and grabed Waganma. Monster pair appears to be looking for Narinki, because of his connection with the Hero Association. Before the pair can leave, Metal Bat prepares to fight them.

Back at the C-City Super Stadium, Saitama attempts to sign in.