The Misfit of Demon King Academy isn't exactly an isekai anime, but it does feature reincarnation. Anos Voldigoad, the Demon King, sacrifices his life before the Hero to end the war between demons ...

Daki is the Upper Moon 6 demon from the Demon Slayer series who was the primary antagonist of the Entertainment District arc. While she was a powerful demon, her brother Gyutaro was far superior ...