Spoiler Summary [Click to show or hide]:
We can call OPM manga Chapter 40.5 a side quest where Saitama and Genos get “personally” hired…
…by the association for a specific mission, both involving cats.
In One Punch Man Chapter 40.5, the story opens with Saitama sitting in a restaurant with a man from the association, begging our hero to find a missing cat.
Meanwhile, Genos is sitting on a park bench when a director from the Hero Association approaches him for a personal request. The person requests Genos to eliminate a specific monster he had been secretly raising, which had escaped.
On his quest to find the missing cat, Saitama becomes frustrated with the poorly sketched cat’s image. Additionally, he deals with the bratty child of the association’s director, who happens to be the cat’s owner.
The child threatens to report Saitama to his father, but Saitama remains unfazed.
On the other side, Genos discovers a bloodstain and follows it, encountering Class A Hero Peach Terry and Class A Hero Heavy Kong lying defeated after battling a monster.
A monstrous cat with multiple eyes, sharp teeth, and long claws attacks Genos from above.
As Saitama continues his search with the child on his shoulder, he approaches a restricted area guarded by Tank-top Blackhole and Tank-top Tiger. Despite their attempts to stop him, Saitama enters, claiming he is on a special mission.
Saitama sees a cat inside the restricted area and witnesses a wall breaking down. Genos emerges from the broken wall, still engaged in a battle with the monstrous cat.
Saitama and Genos briefly meet, but Genos continues the fight.
Saitama and the child leave Genos behind to pursue their quest for the blue-collared cat. Meanwhile, another monstrous cat appears in front of Class A hero Lightning Genji.
Joined by Stinger, they engage in a battle against the creature.
A larger cat appears, prompting Lightning Genji and Stinger to retreat. While escaping, Lightning Genji and Stinger see a girl chasing her cat and rescue her before the monster cat catches them.
The monstrous cat attacks the normal runaway cat, and Saitama intervenes, catching the cat while enduring the strikes from the monster. With a single punch, Saitama effortlessly defeats the monstrous cat.
The child expresses gratitude to Saitama for saving the cat. As Saitama contemplates his role as a hero, Genos reassures him otherwise.
However, the chapter concludes humorously as the rescued cat unexpectedly scratches Saitama’s face.