Arifureta: From Commonplace to World's Strongest (Manga) Vol. 12

To find his way back home to Earth, Hajime set out to conquer all the world's ancient labyrinths, and claim their magic for his own. After taking down the undersea ruins of Melusine, he and his party are enjoying some much-needed beach-side R&R. But that momentary peace isn't fated to last--he soon receives news that his old high school teacher, Aiko, has been kidnapped by Church zealots. Hajime and his party rush back to rescue her, but a fated encounter with the mad god Apostle looms ahead!