In the world of Ronpadang, the Danganronpa Visual Novels are nothing more than that. Visual Novels. Just, in this world's lore, the concept of Ultimates is actually a real world thing. The Danganronpa Visual Novels merely take the concept of "What if 16 ultimate teenagers were kidnapped and thrown into a killing game?" and it turned into a popular franchise.
Although, since you're here, you most likely knew what Danganronpa is.
Ronpadang is a semi-serious parody of Danganronpa. So, the OCs that exist here can reference and acknowledge the existence of the Danganronpa games. It won't be fourth-wall breaking. Ronpadang was created by a rather large group of fanatics. People who absolutely adored the Danganronpa games and spent hours playing each entry. These fanatics were always looking forward to the franchise's next entry.
... Then Danganronpa v3 released, and it was confirmed that the Danganronpa franchise had finally come to a close. No more games were going to be released.
This large group of fanatics didn't use to be one large group. It used to be many, many smaller groups. All scattered around the globe! Then, once the games came to an end, they started to desire more... A more real experience. Then the thought came to several of the groups.
"What if we made our OWN killing game?"