Romans & histoires Meccha Shoukan Sareta Ken

Shantal hears the sky crackle loudly, almost thunderous, and looks up to see four blue dots, all in a line, fall from the sky. Shantal hears the sky crackle loudly, almost thunderous, and looks up to see four blue dots, all in a line, fall from the sky.The ground shakes and cracks as another mech appears, this one with a large machine gun on its back. The chest of the new mech opens, revealing a solider that Shantal has felt like she's seen before, but gets a headache when thinking about it too much.

if I can recall his name is Seisaju he's one of the forth Strongest Kiyosaku. Seisaju : Well Shinjuku we're here. Shinjuku : Yessss Now let the games begin. S1 E10 "Life or Death"