Tempest-King of Mecha

Cael Thorne, the "Mech King" branded a traitor by the entire alliance, renames himself Ash Gray and hides out as a janitor at a mech academy. When Aria Vale, the woman he once saved, is betrayed by her fiancé and trapped in a monster gladiator arena, he is forced to reactivate Orion Zero, the legendary final mech, and return to the battlefield with a perfect 100% neural sync rate.