Jun Ushiro

Jun Ushiro (宇白 順, Ushiro Jun), is one of the pilots of Zearth that takes importance at the end of Bokurano.

Personality
A boy with a short fuse, whenever he is upset by anything, the first thing he does is beat Kana, his younger sister. Ushiro's mother died giving birth to Kana, which would explain his hatred toward her. Later in the series, he begins to develop feelings towards Yōko Machi. Machi's death had him in a depressed state of mind in both the manga and the anime. Being accused of killing Takashi affected him greatly. That's a main reason he chooses to stick with the others in the manga despite not being bound to the contract.

Manga
In Chapter #43, prior to Kanji's fight, Ushiro confides to him that he hadn't joined the contract with the others, revealing himself to be the one who is exempt from the contract. The chair he usually sits on actually belonged to Kana, who had joined the contract.

After Kana's victory, Ushiro enters into the contract along with Machi, wanting to involve himself as opposed to "outsiders". Machi is chosen for the next battle, leaving Ushiro to fight the final battle. But after Machi's premature death during their trip to visit all their friends' families, Ushiro had to take her place for the 14th battle. In Ushiro's fight, the battle takes place on the opposing enemy's world.

Death
After a short battle, Ushiro defeats the enemy robot, but is tricked into opening the enemy cockpit which allows the pilots inside to teleport away and hide among the population of the city. Realizing with horror the enemy pilot does not have any intentions to win the battle or let herself be found, and due to the 48-hour limit rule for a winner, Ushiro has no choice but to kill everyone on the planet. After preparing himself mentally with Dung Beetle, Ushiro launches the start of his genocide attack; he has a short freak out in the middle of it, throwing up on his own lap, but recovers and ultimately succeeds on his attack and destruction of the other planet, passing away shortly afterwards. He is shown to have joined the group of children in a dream sequence.

Anime
Jun is entered into the contract along with the other children at the very beginning. He is eventually revealed to be the orphaned son of Tanaka and Ichirou, a murdered Yakuza heir and a friend of Sakakibara. After Kanji's battle, Koyemshi asks him to ask Kana to sign the contract in exchange for him becoming the very last pilot, who, according to the rules, has a chance to survive the battle if winning. However, Ushiro decides not to involve Kana in the contract, and asks Machi to help him get her free.

Death
After Machi's killing of Dung Beetle and subsequent victory, Ushiro demands Seki let him become the next pilot and destroy Zearth after winning, relieving both of the successor's duty, and potentially sparing other parallel universes from the same ordeal. After a long 30-hour battle, Ushiro manages to defeat his enemy and save the Earth for good, dying alone, but peacefully.

Kana Ushiro
"Your battle is to live on!" Jun to Kana in episode 23

Until later episodes Jun hates Kana a lot. Mainly because he believed his mother died giving birth to her. Whenever he is angry he'd beat Kana. In later episodes he has deep care for her and fought so that she could live on.

Ano Maki
"I wanna slug Ushiro a good one!" Maki to Aiko, Machi, Komo and Tanaka when Ushiro is mentioned.

Maki developed hatred towards Jun at the beginning of the series because of the way he treats Kana. Even to go so far as to attack Jun sometimes. Jun also hates Maki.

Youko Machi
"Look out for Machi" Kanji to Jun about Machi.

Machi despised Jun early on and discusses whether Kana should be taken away from him because of his abusive nature with the others. However later on she starts to understand Jun and even has feelings for him. Jun never shows any feelings like this towards Machi but is saddened by her death.

Aiko Tokosumi
"He's a bastard!" Aiko to Maki about Jun.

Though she despised Jun early on she began to understand him and the two gradually become friends. Jun's reaction to her death isn't known.

Kanji Yoshikawa
''"You wanna know why I never step in when you abuse Kana? It's because she asked me not to." Kanji to Jun about Kana.''

They have been best friends since first grade. In the manga Jun approached Kanji and explained that his mother was dead too and that they should go to his place. The death of Kanji saddens Jun a lot and he agrees to finish the battle once and for all.

Takashi Waku
''"Don't be a downer man." Takashi to Jun when he questions if they can protect the earth.''

Takashi is an annoyance to Jun. Jun dislikes his wacky personality however he does not show any hatred towards Takashi. He shows up to Takashi's funeral and is accused by Kanji of sticking with them all that time because of his guilt despite the fact Jun had nothing to do with his death.

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