Isekai anime almost always follow characters who are transported from one world to another, generally going from the mundane human world to a fantasy world. Some isekai are reversed, where a magical creature or person travels to the human world. Most isekai anime tend to be for a shonen audience, but there are some written and produced for a shojo audience of young females.
Source：https://www.cbr.com/the-best-shojo-isekai-anime/
