Race and Rise: My Machine Girls

In the Mecha Age, girls who turn 18 can transform into mechas and go out to the battlefield, and men can become Pilots who lead them in combat. Ethan wakes up with the talent of an SSS-rank Pilot. The Mecha Girls who come to him differ in temperament and in how they fight, and their weapon and energy systems keep evolving. Each win he takes puts him up against something harder, and the rank he woke up with gets tested in fights where his life is on the line. With enemies pressing him, Ethan has to keep raising his own strength and learn to move in coordination with the Mecha Girls, and he fights his way up from there.