Ikumi is the fourth and last in a successive line of captains aboard the Ryvius, following in the footsteps of such varied individuals such as Lucson Houjou, Aires Blue and - most recently - Juli Bahana.
This, combined with the increasing amount of violence aboard Ryvius and the brutal assault of his girlfriend, made him a coldhearted leader who cannot seem to distinguish between his allies and enemies, even going so far as to shoot his own friend.
Also, she wore her hair down for the last few episodes following her assault, as a testament to the childhood she lost and her newfound maturity; this also makes her resemble Ikumi's sister more.
She sometimes chooses to sleep in a tent inside the ship rather than in the residential area, although this may be to listen to her music in peace and without crewmates asking she turn down the volume.
Having been born and raised on Uranus, where the harsh environment of the planet gave rise to a special form of religion, Fina has a unique sense of ethics based on the followings of her sect's founder, Mother Arne.
At 16, Fina is extremely beautiful, but due to her aloof mannerisms stemming from her beliefs and her standing in the Uranian aristocracy, she is hard to approach.
Not only does her beauty, charisma and demure mannerisms hide an unstable madness, but following her personal creed as mentioned above, Fina is also guilty of murder.
This unfortunately involved Fina killing with her bare hands anyone that reminded her of the past, including her former boyfriend McBain, and her friend Sandy Aren, who was strangled and her body disposed of under the cover of the celebrations of the Ryvius's party in episodes 10-11.
In the last episode Kouji, given the honour of deciding the Ryvius' new first destination, chooses to visit the Uranus vicinity because he has some things he wishes to discuss with her.
Neya (ネーヤ, Nēya); Voiced by: Rei Sakuma (Japanese); Chantal Strand (English) Note: This character is referred to in some material as Neeya.
Team Blue (チーム・ブルー, Chīmu Burū) is the moniker for a martial arts group from Saturn featured in the sci-fi anime series Infinite Ryvius.
The group functions almost like a street gang aboard the Ryvius, and uses violence to seize power and attempt to bring people under their control.
For a time, they were the de facto leaders of the Ryvius, and after their fall some members regained power in successive regimes aboard the ship.
He was suppressing his violent side when on the Liebe Delta, but the Ryvius is a whole new environment and Blue sees the opportunity to unleash his natural aggression and take over the ship.
Fuu Nam Chai (フー・ナムチャイ, Fū Namuchai); Voiced by: Hisao Egawa (Japanese); Michael Adamthwaite (English) A distant relative of Blue's, he is also from Saturn.
Short, both of stature and of her green hair, Michelle laughs a great deal, often chews pink bubble gum, and seems airheaded.
Like her sister, Michelle is adept at seduction, and used her skills to obtain a new wardrobe and the freedom of her fellow Team Blue members from the brig.
The Dive was sabotaged, and was ultimately a failure, with the instructors all dead and the Zwei, as the most advanced students in the Liebe Delta, forced to take control of the station and later, the Ryvius.
In the Zwei for training for entry to the National Defense Academy, Lucson has his family honor and pride to live up to; his father and three brothers are already in the service.
As the second-ranked student in the Zwei after Juli, Heigar acts as an assistant and lieutenant to the leader and captain of the ship, whoever he or she may be (in other words, loyalty to the office and not its holder).
His desire for an utopian society on the Ryvius led to an increasingly harsh regime, to the point where he was willing to turn in even fellow Zwei cadets as so-called 'threats' to the order and control of the ship.
Good Turtleland III (グッド・タートルランド3世, Guddo Tātorurando San-sei), also known as Charlie (チャーリー, Chārī); Voiced by: Toshiharu Sakurai (Japanese); Alex Doduk (English) Joining the Zwei at his parents' request, this chubby boy of 16 years is timid and sheepish despite his great name.
This selfless act thawed out Criff's cold heart, and she became considerably warmer to him, even choosing to stay by his side when Michelle offered her a chance at freedom.
Carabona Guinea (カラボナ・ギニー, Karabona Ginī); Voiced by: Omi Minami (Japanese); Alison Raine (English) The second of three female Zwei cadets, she is the mousy-haired, slightly square girl who also appears to be the Ryvius' communications officer.
She seems to have a flair with designing and making clothes, as she made a number of outfits for the various students on the Ryvius to wear for the ship's party, and also created Ran's cheongsam dress.
When the space station collapsed, Mr. Campbell perished attempting to save the lives of all the students aboard, and Pat went through the terrible experience of losing a parent.
Timid by nature, Reiko proves to be selfish and cowardly in a hostile situation, when Kozue was ganged up on and attacked by several other girls for being the girlfriend of an "unlimited points user".
Johnson Cole (ジョンソン・コール, Jonson Kōru); Voiced by: Tomoharu Sakurai A 16-year-old boy, Johnny appears to be the clumsy nerd character of the show.
He first appears in the third episode when, thinking that everyone was going to die, confessed his feelings for Charlotte Lakunes (シャーロット・ラキュナス, Shārotto Rakyunasu) (Voiced by: Megumi Toyoguchi), a fellow girl classmate in front of everyone, only to be embarrassed when she shot him down (although she did it gently).
First seen in episode three when the two sneak into a storage closet to make out, only to be "rudely interrupted" when the Zwei order everyone to evacuate when the Libra Delta begins to sink.