Arifureta: From Commonplace to World's Strongest (Manga) Vol. 8

HIGH SCHOOL REUNION\nHajime’s old classmates are in deep trouble, cornered by demons in the depths of the Great Orcus Labyrinth. Closest of them to Hajime was Kaori Shirasaki, who has long lamented her inability to save him from falling into the dungeon’s abyss. When he arrives to rescue the class, she can finally see just how much he’s changed—the commonplace otaku is now a ruthless, unstoppable killer! Can Kaori still reach the hardened heart of a man who’s become the World’s Strongest?