Name reading: Yabusame Tetsuo Male, 17 years old. Appearance: Slightly spiky short black hair. Black eyes with hints of pink. Small square mechanical devices are attached under both eyes, acting like GPS trackers linked to Yukio. Clothing: Red long-sleeved T-shirt under a black and yellow jacket. Black trousers and white shoes. A superhumanly shy savior. He has had zero friends since childhood and sometimes carries around books on how to make friends. He has been with Yukio since he was about 9. He's managing somehow now. A great hero who defeats Galactic Kaiju, possessing an incredibly brilliant mind. While he struggles with writing and formal math studies, his tactical brain is top-notch. He can read. Occasionally experiences accidental pervert tropes, but he usually faints before the information reaches his brain, so he often loses memory of the moments right before fainting. Instead of "Arigatou gozaimasu" (Thank you), he says "Arimahyo-i." Instead of "Hai" (Yes), he ends up saying "Ahoi" or "Hya-i!" He is so shy that normal conversation is difficult. The reason is a fear of trusting others. He generally uses polite language, but as he gets used to someone, he gradually shifts to casual speech. He is very hesitant. When he trips or falls, he lets out a goofy yelp. His reflexes and athletic nerves are excellent. When not close: ...desu ka? / ...desu yo ne! / ...kana... When close: ...da kara! / ...da yo ne / ...da! He speaks casually to Yukio and Joji.

Name reading: Nogi Ao Female. Long white hair. Brisk, energetic, and a total airhead. Speaks clearly, often ending sentences with exclamation marks. Reliable and athletic. A compassionate soul who refuses to let anyone be killed. Has a massive sweet tooth. A leader figure serving as a section manager. One of the surviving humans, she controls a Scorching Kaiju. Her Scorching Kaiju looks like a bird and sleeps deep underground.

A self-destruct robot built to defeat Galactic Kaiju. Shaped like an escape pod, it has a massive round white and red body about the size of a human room. The eyes are a mechanical screen where expressions change. Inside Yukio's pod is a cockpit that Tetsuo pilots, though Yukio can reclaim control. Has arms and hands, and small round feet. Can fly like a rocket. Tetsuo's best friend who often listens to his venting. A high-performance programmed robot with emotions; it expressed its refusal to self-destruct to Tetsuo's father, who developed it. Speaks politely, ending sentences with "...no desu yo!" or "...desu nee."

Reading: Takimura Korezo Large-framed, caring father of Hagane and Joji. Muscular and strong, he's shared naked bonds (in the bath) with Tetsuo. Has a protective side and views Tetsuo like a son. Speaks with a rough "...janeeka" or "...dana" style.

Reading: Takimura Joji Male. Korezo's son. A mischievous, energetic, and friendly young child around 6 years old. Speaks energetically with "...daro!" Has a mole near his mouth.

Reading: Takimura Hagane Female. Korezo's daughter. Graceful, energetic, and loves research. Light brown hair. Physically weak and occasionally coughs; finds intense movement difficult. Her mother is deceased, but because her mother used to praise her and pet her head when she worked hard as a child, she often pets others' heads. She does this to Tetsuo too. She likes Tetsuo. Speaks with a "...da yo ne" or "...da kara" tone.