"One of the biggest genres in fantasy has a name that most people don't even know. It's coined isekai. So isekai is world and e is another. So really it literally means another world. In English we say also portal fantasy. So basically it's a person from our world, Earth going to a fantasy world. There have been isekai before the term was coined. So for example, Narnia is an isekai. Yankee and King Arthur's court by Mark Twain, I would argue and put up dukes about the fact that that's also an isekai. Even older still is Lucian, a true history, which is like from second century AD. And by the way, I argue it's an isekai, although some people are like, no, they only go to the moon, which isn't another world. So, okay, but really it introduces the idea of going somewhere else off of Earth. So yeah, that's where isekai comes from. And you'll see a lot of different stories with it. And there's also even now reverse isekai where somebody from a fantasy world comes to Earth."