Nitro (ニトロ) is one of the Last Galerians who is bored with the world and cares about absolutely nothing. She is completely cold-hearted and seems to find amusement in destruction and pain. The only female of the Last Galerians, Nitro possesses the power to create illusions and weave fantasy worlds where any dream or wish can be realized. A master of trickery, her skills in deception are only matched by her perfection of pyrokinesis. Nitro can protect herself with multiple orbiting fireballs which regenerate over time, summon firewalls, homing flame serpents, explosive meteors from the air, and can dance into a fiery pirouette. She also tends to use frequent teleportation and levitation to avoid her enemies. Nitro questions the concept of reality during her second battle with Rion, showing a philosophical and nihilistic personality. Unlike Parano, she is more comparable to an emotional sadist than an indiscriminate killer.
One of the more noticeable things about her appearance is that she wears her ponytail facing forward, often times covering half of her face, as opposed to the back of her head as they are usually worn. She is voiced by Michelle Ruff in English and by Yukana in Japanese.
Nitro is first seen with the rest of her comrades after Ash and Rion's first meeting in the uranium refinery. She expresses her amusement towards Parano arguing with Ash and mocks him for threatening to kill him. Afterwards, Nitro decides to attack Rion next as she is the only Galerian who he doesn't know yet.
She encounters Rion in the dome area of the Mushroom Tower in the data world where she questions Rion's aiding of humanity, despite the fact that the world is destroyed and near beyond saving. He attempts to answer but is cut off by the Last Galerian and then after a few more words, initiates the fight. Despite her efforts, Nitro loses the fight and comments that he is more stubborn than she imagined. Right before vanishing away, she says she'll show Rion the true meaning of despair the next time they meet.
Nitro is later seen during Parano's return from combating Rion a second time. She is there to watch Parano's execution and expresses no feelings or words at all. Spider does make a comment about them being all friends, but she gives no more than an indifferent turn of her head.
After one of Rion's many trips to the Data World, he returns to the military base with many people acting strangely. Romero apologizes to Rion for doubting him and finds out that they've had success in repelling the Galerians. He then meets Cas who requests him to retrieve ammo and while returning, he sees a vision in his head of Cas dying. Rion tells Lilia about his "nightmare" to find out it wasn't real. Lilia then begins to act strangely and asks Rion odd questions. The entire event is then revealed to have been an illusion of Nitro posing as Lilia, created solely to trick Rion.
He tells him the nightmare he had was sent by Lilia and that they couldn't prevent it, thinking that her telepathy faded years ago. Rion demands to be sent to the real world but Nitro denies reality, asking how can anyone prove it was real. Nitro expresses to Rion that no matter what is lost, "sadness means nothing" and that she can create an infinite amount of worlds to live out any desire. In exchange for the chance to delete the virus program in his mind, she offers to create one for Rion. He refuses the offering and Nitro then decides to kill him instead.
Defeated, Nitro attempts one last deception and mimics Lilia once more. It doesn't work the second time but in the confusion, she teleports behind Rion and presses a gun toward his neck. While saying that she always wanted to see the despair in his face, Nitro is caught off guard and Rion releases himself from her grip. While choking her, Rion begins to supposedly upload the virus program into Nitro. During her last seconds of life, she tells him her regret and that she would have liked to die in the real world. Right before she is killed, she attempts to trick Rion one last time, but it is too late and she perishes.
Nitro appears one final time during Ash's breakdown in the middle of his fight with Rion in the virtual world. She reveals that she was born from Ash's despair and refusal to do anything about his plight. Her carelessness and sadism could be explained as a result of Ash's suffering under Dorothy. This also can explain the use of the Hate password in the Mushroom Tower as the last letter in his name (Anger and Sadness being the other two). Ash cannot apparently handle what he is hearing and tries to kill himself, but he is unable, becoming much more stronger than before and absorbing Dorothy for additional power.
Like the rest of the Last Galerians, she most likely vanished from Ash after his loss to Rion and their deletion by Pat that would follow ten years later.
- Nitro's name is a shortened form of nitroglycerin, an explosive compound used in dynamite. It is also used in the medical field to treat people who have angina (heart pain).
- A glitch can be triggered during both fights with Nitro in Galerians: Ash. Occasionally, when Nitro descends from the air she will repeat the same action and clip through the floor. She will quickly teleport to the surface of the floor after the animation is finished however. In both instances, the player was locked in on Nitro but it is unconfirmed if this is a requirement to trigger the glitch.
- Nitro battling Rion in an arena of full of darkness is similar to the battle between Rion and Cain. In both battles, the radar map is unavailable and in Nitro's case, it makes her slightly more difficult to keep track of because of her quick teleportation.
- Nitro shares some features with Phantasos, a minor antagonist from Saint Seya: The Lost Canvas, especially the anime version: both are female members of a group of four enemies, able to exist in another world outside the real (Data World and Dream World), become ultimately part of their leader in some way, are skeptical if reality is necessarily better than fantasy, fight at a certain point in an extensive, almost empty area (Nitro in Data World, Phantos in the place she rules, Phantasy, the kingdom of beautiful dreams), have the ability to disguise themselves and to trap their opponent in a dream world able to satisfy every desire she can have. They both try to tempt the protagonists they face with this power, but their victim ultimately frees themselves saying they don't actually have any desire. However, Nitro is more skilled in psychological war, disguising herself like Lilia, while Phantasos uses this power only for vanity. Also, unlike Nitro, Phantasos is actually male, who likes to disguise himself as female.
- Nitro is similar to Rainheart: both have the ability to create mental illusions and are masters of pyrokinesis. Still, it's never revealed how much of their power is real or just in Rion's mind. In Nitro's case, it's impossible to define this, since she is never seen acting outside the Mushroom Tower, a place made of data, that she can arguably manipulate at will. Considering that Lilia mentions Nitro in passing as one of Ash's three lieutenants, the human military must have battled her at least once in the real world. Perhaps she can use her fire powers in both the real world and in her own illusions.
- Nitro has the ability to teleport, like Birdman, during her boss fights and cut-scenes. However, she is not untouchable when she performs it. If the player is able to hit her and if closely examined, she seems to move very quickly rather than immediate teleportation. This can explain why she doesn't try to teleport to escape Rion's final attack at the end of their second battle, instead she trying to trick him by pretending to be Lilia again. Regardless of how her teleport ability works, Nitro couldn't escape from Rion after the second battle.
- Nitro is the only Galerian that doesn't leave a dead body behind. When Rion destroys her in the data world illusion, she simply disappears into nothing.
- Rion's relationship with Nitro looks to be the opposite of the one he has with Rita, the other female Galerian: while Rion, albeit unintentionally, attacked Rita personally by killing her brother Rainheart, in Galerians: Ash it is Nitro who personally attacks Rion using Lilia and playing with his feelings. Also, while Rita is the Galerian that was shown more sympathy from Rion, Nitro is arguably the Galerian, at least in the sequel, that Rion showed more contempt, killing her with a wrath in his eyes and voice he never shows so openly towards Parano and maybe neither to Rainheart.
- Nitro is one of the few Galerians, alongside Rainheart (at first) and Parano, who don't receive compassion by Rion. This can be because they show great pleasure to kill people and cause pain. However, Rainheart was brainwashed by PPECs, and Parano and Nitro were "born" the way they are. Also, while Nitro shows some kind of sadism towards Rion, she is never showed to kill or enjoy it. She looks to be more interested in mentally breaking Rion, rather than outright murdering him. Part of her dialogue suggests that she enjoys pain so while she may enjoy killing, she is not obsessed with it like Parano. It's unknown if Rion retains these feelings until the end.
- During her boss battles, Nitro uses dancing and gymnastics during some of her attack animations. Her spinning flame attack during her second phase begins with a spin that leads into a pirouette, a dance move in ballet. Also, Nitro will go into a cartwheel before unleashing her homing fireball attack.