Trash Mech to SSS: My OP System

The Story

He transmigrates into a new world only to face a bitter betrayal because his combat power is too low. Fate shifts dramatically when he awakens a god-tier ability to upgrade broken-down mecha-girls to SSS-level or higher. His journey begins with saving a dying, E-level mecha-girl. Armed with this incredible power, he sets off on a relentless path of revenge. The road to the top is fraught with unknown challenges as he seeks to overturn the injustice he suffered.