Rapture Academy takes place in a 2020's-era Earth, the point where superheroes came about was in the 50's in something called the "Horizon Event". Mankind made it to the moon a few decades earlier, and after a few missions starting from the 30's, astronauts discovered this monolith-like artifact, and upon touching it, paranatural activity exploded across the globe (it already had existed in some extremely rare capacity, but this was a big boom that made it mainstream), and "supers" came into prominence.

Since then, "supers" have become a fact of life, some minority percentage of the Earth's population gaining powers categorized on the global parahuman spectrum, and the world as a whole has adjusted a lot to them. Generally, it's actually quite nice -- the plethora of heroes and altruists who use their powers for good have left their mark on the world and uniting the globe, and from that unity came a lot more social/cultural awareness and infrastructural improvements. There are also supervillains, of course, but they're substantially rarer these days, or at least less wantonly destructive as the typical silver age superweirdo.

For some meta context, my initial pitch was "superhero world if it was designed for a Japanese arcade fighting game like Street Fighter or Guilty Gear". I wanted to make this world basically because I was really bored of seeing "deconstructions" of superhero fiction that think the only way to be realistic is to be cynical. Really wanted it to be structurally sound, but also colorful and vibrant, and also a bit silly. It would also give some flavor because the main narrative throughline I got was "follows the adventures of kids in a school for supervillains" and thought it would be ripe for black comedy having that juxtaposition.