Yōsuke Kirie

Yōsuke Kirie (切江 洋介, Kirie Yōsuke), is one of Zearth's pilots.

Character
Kirie's cousin Kazuko, who is suicidal, makes him wonder about the worth of his life and that of others.

Manga
When Isao Kako tries to flee from his battle with the enemy robot, Kirie makes a comment implying that Kako is a coward, causing him to snap and attack Kirie. Kirie is continuously beaten by Kako until Chizu steps in and stabs Kako in the neck, killing him. She then makes sure that Kirie knows that she did not do it for his sake, but rather, for her own.

After Chizu's battle he talks to the teacher who had abused her, and ends up stabbing him with the knife Chizu had given him, though the wound is not fatal. Because Kirie had decided to talk to the teacher, who taught at a different school, he ended up bringing the teacher to the conclusion that all of the students who went on the nature trip over summer have something to do with Zearth, which eventually ends up putting all of the children and their families in danger.

Kirie discusses his views on the lack of importance of individual human lives with Tanaka, as well as about sacrifices. He wonders if he can bring himself the courage to fight and kill another human, even knowing that the entire world's fate depends on it, and asks Tanaka to kill him and replace him if he fails to do so.

Before his battle starts, he has Dung Beetle teleport him onto Zearth's arm, revealing himself to the opponent robot. Its pilot, a girl who looks exactly like his cousin Kazuko, does likewise, showing him the many scars along her arm. After this moment, Kirie finally finds his resolve to fight.

Anime
After being chosen as the next pilot, Kirie discovers his mother attempting suicide after months of unemployment and abandonment by her husband. Growing angry at the world that drove his mother to try to kill herself, he refuses to fight when it is his turn. However, his opponent commits suicide in front of Zearth, ripping out and crushing its own cockpit. Since Kirie refused to use Zearth, Zearth did not use any energy, which is supplied by the life force of humans, resulting in Kirie living through the battle. However, since he was chosen as the pilot, and is still not dead, he will continue to be the pilot for Zearth's following battles.

During the period between his two fights, his father returns to his mother after receiving news of her suicide attempt, and Tamotsu helps her find a job as a waitress. Seeing the world give his mother another chance at happiness, he decides to give the world another chance as well, which cements his resolve to fight in his second battle. Kirie is revealed to be a natural in piloting Zearth as he quickly and swiftly overwhelms the enemy robot. Before dying, Kirie confirms his suspicions about Machi and unveils her true identity as Dung Beetle's sister.

Isao Kako
Kako abuses Kirie many times throughout the series but still remains Kako's friend.

Jun Ushiro
It's not known whether or not they became aquaintanced but Jun complimented Kirie's fighting style saying 'He Might Just Be The Best Out Of All Of Us'

Chizuru Honda
They know each other since they attended the same middle school.

Zearth Pilots
Characters who are either known to have piloted Zearth at some point or have been specifically considered to pilot it at some point.

Alphabetical order
01 Aiko Tokosumi | 02 Chizuru Honda | 03 Daiichi Yamura | 04 Isao Kako | 05 Jun Ushiro | 06 Kana Ushiro

07 Kanji Yoshikawa | 08 Kokopelli | 09 Kunihiko Moji | 10 Maki Ano | 11 Mako Nakarai | 12 Masamitsu Seki

13 Masaru Kodaka | 14 Misumi Tanaka | 15 Takami Komoda | 16 Takashi Waku | 17 Yoko Machi | 18 Yōsuke Kirie

Chronological order
01 Kokopelli | 02 Takashi Waku | 03 Masaru Kodaka | 04 Isao Kako | 05 Chizuru Honda | 06 Daiichi Yamura

07 Mako Nakarai | 08 Kunihiko Moji | 09 Maki Ano | 10 Yōsuke Kirie | 11 Aiko Tokosumi | 12 Takami Komoda

13 Kanji Yoshikawa | 14 Yoko Machi | 15 Jun Ushiro | 16 Kana Ushiro | 17 Masamitsu Seki | 18 Misumi Tanaka