[...oh, right. We're kind of getting ahead of ourselves, aren't we - ]

It's a bit of a long story, Togami-kun...but the most concise explanation is that it's a different world entirely. We don't know how we got here, but there are several of us from Hope's Peak Academy present already; from what we can tell, this world is both real and safe inasmuch as no one seems to be trying to kill us!