Kazuki is persuaded by UN Inspector Akane and Ken to be Hartzenen's pilot. Only females can pilot the robots, so they are amazed that a male can activate one. Kazuki meets the alien D. Kazuki practices using the robot and he pilots Hartzenon in battle with Mitsuki and D. He is terrified at first, but when D and Mitsuki are in trouble he forgets his fear and springs back to life to save them.