Isekai Quartet

What happens when you shrink four of the biggest isekai casts in anime — Overlord, KonoSuba, Re:Zero, and The Saga of Tanya the Evil — down into chibi form and dump them into a high school classroom together? You get Isekai Quartet. A mysterious red button appears in each of their worlds, and because nobody in anime can resist pressing a mysterious red button, they all end up trapped in a school setting where Ainz Ooal Gown has to sit through classes alongside Kazuma, Subaru Natsuki, and a tiny rage-filled Tanya Degurechaff. The comedy comes from watching these characters bounce off each other in ways their own series would never allow. Kazuma trying to recruit Darkness-level masochists from other shows, Ainz awkwardly pretending to be a normal student, Rem being aggressively devoted to Subaru while everyone else just watches — it's all played for laughs with zero stakes and full self-awareness. Each episode is only about 12 minutes, so the whole 12-episode TV series goes by fast. The chibi art style from Studio PuYUKAI keeps things light and goofy, which fits perfectly since this is pure parody. If you liked Attack on Titan: Junior High or Kaginado, this is the same energy — beloved characters in a low-key setting just being ridiculous. You'll get more out of it if you've seen at least one or two of the source shows, but honestly, the character dynamics are funny enough on their own.