The man who was once the strongest sage was reborn through reincarnation as a six-year-old boy named Eddy.

Inheriting memories of his past life and obtaining power even greater than before, Eddy makes a single resolve.

――In this life, instead of being noticed as the strongest sage, he would walk a path in the shadows.

Burying the past where he one-shotted the Demon Lord, Eddy enrolls in the Royal Academy to live as an ordinary six-year-old.

Of course, he keeps hidden the fact that, after the Demon Lord's demise, he reigned as the ruler of darkness――.