Kawaguchi published her first manga at 13. Now 6 years have passed and she has yet to produce anything else. Thinking she doesn't have enough experience to write about anything, she decides to change that. Noticing that boys' love and girls' love manga have been popular recently she decides to ask a former co-worker out to get some inspiration. Her penname is ��明日香 (same reading).
In the anime, it is revealed that Maira, a former Pawn, became a Bishop by gaining the ÄRM Vaqua. He is not given a backround in the manga. Maira is a black-cloaked masked man who takes pleasure in engulfing and digesting people with Vaqua. Vaqua is a blue/green slime-like Guardian ÄRM with one eye. Maira is first seen watching the War Game battle between Ginta Toramizu and Garon. During the second round of the War Games, Maira reappears as a fighter for the Chess Pieces. He has the last of the battles in that round, and goes up against Dorothy. Maira is quick to falsely judge Dorothy's power, though he easily destroys one of her weaker Guardians and stalemates another. Dorothy, however, calls back this one to bring about her favorite, Toto, which eats Maira's Vaqua. Maira, now ÄRM-less, begs Dorothy for mercy. Dorothy, however, doesn't do as such and has Toto eat Maira as well, becoming the first casualty of the War Games.
A member of Arc Aile who, like Cisqua, chose to use weapons rather than Edel Raid, Maina is an old friend of Cisqua. She appears in an episode of the anime to bring Ren back to HQ as the main Arc Aile trio uses the disguise of a vacation to help find Edel Garden. It turns out she was controlling a Sting Raid that was attacking people on the ship through song, but in the end Cisqua uses the song against her and has to kill her to prove her dedication to Ren. Cisqua also claims that Maina is the better sniper, but worse at everything else.
Maina is the mother of Moena and part of Angel Blade.
Akio is Nagisa's father. Although he often talks and plays rough, he is kind and sympathetic. His childish side makes it easy for people to befriend him. He runs the Furukawa Bakery with his wife Sanae. In his spare time, Akio plays baseball with children in the small park next to the bakery, and indulges in the Gundam fandom. He is often the victim of Sanae's bread, having to eat her bread in front of her while claiming that he loves it. During the School Life arc, Akio reveals that he was an actor in a theatrical company, but has to quit his job due to Nagisa's health. Akio replaces Youhei's role as the comic relief during the After Story arc, however, he can be serious when needed, as he often gives advice to Tomoya on what it is like to become a man. He tells the story about how Nagisa almost died due to their unintended negligence, and how her life is connected to the city after getting saved from her fever.
Kouko is Fuuko's older sister. She used to be an art teacher at Tomoya's school, and she treats everyone kindly. Kouko is one of the familiar faces in the Furukawa Bakery, and Nagisa admires her very much, being her former art teacher. Currently she is engaged with Yusuke Yoshino, and is the major reason why Fuuko still exists in the school, despite still sleeping in the hospital. In the movie, Kouko was a drama teacher instead of an art teacher. She, along with Youhei and Tomoya helped supervise and revive the drama club for Nagisa.
Macha is the cat character that appears in .hack//SIGN and other .hack series. Although she appears to be a typical hacker or Vagrant AI, she is actually an alternate form of the Sixth Phase Macha the Temptress. She lures Tsukasa to a secret area, where Morganna can then manipulate him. After the events of SIGN she takes on the form Mia who resembles an older version of herself dressed as a warrior, and goes on adventures with Elk to find aromatic grass because Elk resembles the boy in her dreams(Tsukasa) who gave her aromatic grass in the first place. In .Hack//GU Endrance(an adult Elk) has the power to summon her true form into battle.