He Became A Powerful Immortal After Being Betrayed

Haruto Tokishima was experimented on since a baby by his father to create a God.
One day his academy gets suddenly attacked, making him see his childhood crush vanish in front of his eyes.
Haruto gets immediately thirsty for revenge and enters a mecha robot to fight back, but in order to activate the mecha he's requested to resign humanity.
Haruto quickly quits being a human and destroys the enemy.
But when he gets out, one of his classmates stabs him in the heart, without knowing Haruto became an immortal.

Anime:Valvrave