Isekai Quartet

The protagonists and other charactes of four anime series—"Re:Zero kara Hajimeru Isekai Seikatsu", "Kono Subarashii Sekai ni Shukufuku wo!", "Overlord" and "Y?jo Senki"—in where they are transported each one magically to another world are all summoned—in different and comical ways—to a High School, there, they are forced to complete a whole "school year " in order to travel again to their respective worlds. This is a "chibi" parody and all the characters interact between them in such a way.