The Misfit of Demon King Academy: History's Strongest Demon King Reincarnates and Goes to School with His Descendants Volume 2
魔王学院の不適合者 ～史上最強の魔王の始祖、転生して子孫たちの学校へ通う～, Maou Gakuin no Futekigousha: Shijou Saikyou no Maou no Shiso, Tensei Shite Shison-tachi no Gakkou e Kayou
What if you were the strongest demon king in history...but nobody believed you? A light-hearted action rom-com series wherein the devil is definitely not getting his due.