Saikyou no Kensei to Kenja no moto ni Tenseishita Ore wa Mujikaku Musousuru最強の剣聖と賢者のもとに転生した俺は無自覚無双する; I Reincarnated Under the Strongest Swordmaster and Sage and Unknowingly Became Unrivaled

The series follows a salaryman who is reincarnated into an alternate fantasy world as Rain, after sacrificing himself to save a child. He is saved, however, by two famous beauties who are the most feared across the land. Rain's school life begins even as he already leveling up with the cheat skills of both sword and sorcery.