Fujiki Washiro

Having lost his beloved lifelong master Altesia, Kaltz vowed to take revenge on those who framed her. After making all his preparations, he "returned" to the past. Now 10 years old, and armed with the knowledge he gained in the future, Kaltz begins to operate behind the scenes as the "True Mastermind."

In a world ravaged by war and conflict, Hero Raid Freeden and Sage Eluria Caldwin clashed time and time again over fifty long years as the strongest soldiers of their respective nations. However, their long-standing rivalry came to an inevitable yet bitter end with Eluria's sudden death. A thousand years later, Raid finds he has been reincarnated—and so has Eluria! The world may now be at peace, but the two have an unsettled rivalry between them and the mystery of their reincarnation looms ominously over their heads. There's so much that needs to be done, so they decide to... get engaged and attend the Royal Institute of Magic together?!Official English Light Novel