Originally a robotic space cop known to the rukeitai as a "pursuer", Junk's body was destroyed during an encounter with a Rukeitai. His severed head called out to Sadamitsu and, once worn as a helmet, empowered the youth enough to stand up to the superhuman strength of the Rukeitai. Junk gives Sadamitsu the ability to fly and covers his body with a "material guard", which greatly dampens enemy attacks. Also, to take advantage of Sadamitsu's proficiency with a wooden sword or "boktou", Junk has Sadamitsu fire his activator at a lightning rod, which turns it into a sword shaped activator.

After accumulated damage makes Junk break down completely, the vulture donates some of its energy in order to recharge and upgrade his systems. His new form sports a material guard several times stronger than before, and unlike his previous form, Junk now turns all of Sadamitsu's clothes into a outer layer of armor. His left forearm becomes a rienforced shield, the right arm contains a piercing tazer weapon, and his armored coat contains several thrusters for sudden bursts of speed. The most notable aspect of Junks upgrade is that his "horns" are slightly angled and no longer broken.

Junk has a hard time adjusting to Earth's, or rather Japan's culture and language, especially where Sadamitsu is concerned. His long-winded and technical explanations usually confuse or exasperate Sadamitsu, and so Junk often has to dumb-down his explanations for him to understand.

While his name is unknown, Sadamitsu refers to him as 'Junk', due to his body being mostly destroyed, while other characters simply refer to him as 'Helmet', 'Helmet-san' (Mr. Helmet) and the like. Voiced by: Kazuhiro Yamaji (Japanese), Sean Schemmel (English)