Ken

A rogue Robot pilot who makes it his life mission to defeat the Mimetic beasts after the loss of his wife. While trying to find the Mimetic Beast that took his wife, Rosa, he can be heard yelling, "You're not the one!" to every Mimetic beast that he destroys, eluding to the Mimetic Beast that took Rosa. He doesn't learn of her fate until later on in the series. He is often referred, by the world at large, as a "Menage Zero", a code name for a rogue robot acting without authority. He later takes Lou in when she begs Ken to teach her to be a pilot. He gets infected by the virus that almost every male pilot gets. He ejected Lou from the Celleblader out of the Gainer before Ken dies in his last battle. He attacks the Super Mimetic Beast to reveal its weakness to Godannar to finish it off.

from wikipedia