Seiken Gakuin no Makentsukai

In a world where demon lords reign and humanity struggles for survival, the most powerful of them all, the Demon Lord Leonis Death Mana, makes a desperate gamble. Before falling in battle, he seals his own body and soul, hoping for a future rebirth. A thousand years later, he awakens not as the fearsome overlord he once was, but as a ten-year-old boy, his memories fragmented and his power diminished. Now in an unfamiliar era, Leonis finds himself under the care of Riselia, a young girl from a sword academy dedicated to fighting the very demons he once commanded. As he navigates this strange new world, he must conceal his true identity while slowly regaining his strength, all while unraveling the mysteries of his past and the new threats that plague the land. His ancient power may be the only hope against the encroaching darkness, but can a former demon lord truly become humanity's unlikely savior?

✦ AI-drafted summary