An ordinary person transmigrates to a world filled with monsters and superheroes. His ultimate goal is to become the strongest because he knows absolute strength is essential. After all, the world he had arrived in was the most dangerous world of the One Punch-Man universe.

But thanks to obtaining the "Universal Gift System" that grants him the ability to obtain gift boxes whenever someone thanks him marks the beginning of his unparalleled and domineering rise!

The gift boxes contain various abilities and items, and their value is determined by the kind person who expresses his gratitude to him.

While collecting gift boxes and accumulating abilities, he journeys to Z City. The place where it would begin a whole new Era of the Heroes in three years! He realizes that to surpass the limits of human strength, he must obtain the abilities of heroes and strange beings. Fortunately for him, his luck only skyrockets when he encounters the favorite Saitama, the story's protagonist, in peril. Soon after saving him, he earns the Saitama's gratitude, which helps him gain the best of the Gift boxes—a Diamond Gift Box. This gift box gives him the most powerful ability that unlocks his potential without any limit.

With his limitless potential and Saitama as his disciple, he rises to the apex of this dangerous universe, but how? Well, let's just follow alongside his journey to find out!

C587 I Can't Let Your Wife Down!