Neko is a female Strain and also a Silver Clansman. She is extremely attached to Yashiro Isana and is responsible for altering his memories, as well as those of the Ashinaka High School student body
Neko is a short, but slender girl with long, bright pink hair reaching down along her back and down past her knees. Her hair is split near the middle and is quite messy. Her eyes are shown to have Heterochromia iridum, with her right iris being colored blue while her left iris is colored green. She wears three golden bells: one on her left ear as an earring, another attached to a red collar around her neck, and the last one being attached to another red collar on her right ankle.
While in her cat form, Neko's fur is colored a light pink. She has a small, hot pink nose. Neko's eyes are completely round and flat with two eyelashes sticking out from both. In addition, her red choker with the golden bell retains its form.
She is carefree and playful, having fun when playing games with people or robots. Neko is also quite gluttonous. She is constantly hungry and will whine when she is not being fed. Her taste for food is also very picky, though she appears to favor fish and spicy rice crackers. But even when given food, she does not mind her manners and makes attempts to ask for more or steal others' food. Neko is also incredibly naive, deliberately plunging a flying helicopter, in which she and two others were passengers of, straight towards the engine of the Himmelreich simply to get to the destination faster. Even while performing such activities, she does not take notice of the actual dangers she is causing and instead interprets her actions as "helpful" and even entertaining in her perspective.
Neko is a very childish person, bordering on extreme selfishness. Upon meeting Yashiro, she intentionally implanted memories that led him to believe he was living a life that was never true, claiming that because she found him, Yashiro was rightfully hers. As a result, Neko was reluctant to reveal their first memories of each other, even more so when he asked to remember his life from before then, as she believed he would disappear if he remembered.
Neko has a rather immodest side to her personality. She prefers to go about nude as she claims that clothes are too restricting.
Neko was a victim of the Kagutsu Crater. Her name is only depicted as "XX", and she lives with her parents. XX was a bright, intelligent girl who learnt how to control her powers at an early age, and also underwent mental development check-ups. One day, the person in charge of her check-ups explained the full extent of her powers, and the effects even she was not aware of that it had.
XX had used her power to change her 'parents' memories. Her 'parents' actually lost their son in the Damocles Down, and Neko filled in the spot of their deceased son. Devastated by this news, XX lifted the illusion off her 'parents', who now regarded her as a monster. XX remembered a story her 'father' told him as a child about a cat, and soon then decides to live like the cat in the story, who could live independently and happily. She then gave herself the identity of Neko.
She later lived on the campus of Ashinaka High School, frequently stealing or hiding from the occupants or robots. As such, she was active during many of their school-wide activities, such as the production night on on December 7. While in her cat form, she witnessed a male student named Mishina confess his love for the student council's Kukuri Yukizome
Sometime later, she decided to head to the school's gymnasium near the outskirts of the campus, where she takes a nap. While there, a young man suddenly fell through the roof and onto a thick mat, furthermore unharmed in any way. Frightened, Neko fiercely hissed at him. However, she quickly developed an attachment to the stranger and went over to him, letting him caress her fur. They are soon discovered by Kukuri, who asks for the young man's name. Unfortunately, he is unable to recall it. A concerned Neko then decides to use her memory-altering powers to give him a new name: Yashiro Isana.
Neko passes by Kukuri and two male students, naked, while they're walking around campus. None seem to notice her, however. Neko doesn't care and playfully jumps around the nearby stairs to the rooftop.
At some point, she transforms into a cat, and meets Yashiro Isana. She finds him on the rooftop and eats some of his lunch. Neko proceeds to spend the rest of the day with him, following him to class, even to the city. Her attachment to Yashiro remains even after a pursuit made by several HOMRA members, Kuroh's following rescue of him, and his return to his school's dormitories.
Tired from his day's chaotic events, Yashiro lies on his bed, talking about the video. Neko, lying on his bed and now in her human form, sleepily says that things have been so good and peaceful until recently. Her presence, coupled with her nudity, overwhelms Yashiro. Neko does not react to his shock and, upon being asked, introduces herself.
Neko is then asked to put on Yashiro's jacket but she refuses, saying it's too restricting. He attempts to put it on her anyway, but Neko counters with her illusive abilities, assuming that now they'll be in a game of tag. Yashiro is unable to respond, as he is then attacked by Kuroh Yatogami; seeing him in danger, Neko stops Kuroh and grabs Yashiro's arm, running away from the room with him.
However, after Yashiro throws his jacket on her, Neko starts turning things into a chase, with her being followed by Yashiro who's being chased by Kuroh. Throughout the event, Neko constantly uses her abilities to distract the two teenagers, thus extending the little "game". The chase ensues throughout the evening, night, and even the next morning. By dawn, Neko and the others have become exhausted and hungry, so Yashiro decides to make breakfast. She persists that he doesn't include certain ingredients in the soup he's making. However, Kuroh ends up making the food instead for the three of them.
Throughout breakfast, Neko constantly forgets her table manners and just stuffs herself on Kuroh's food. However, she attempts to thank for her meal when she sees Kuroh and Yashiro do so, only she thanks for the "meow" instead. Afterward, Kuroh attempts to kill Yashiro again, causing Neko to jump from her seat and hiss angrily at him. He asks who she is and Neko reintroduces herself. She states she does not understand Kuroh when he asks if she is a Strain. Neko does state that she is Yashiro's cat and that Yashiro is hers, causing her to jump about happily.
The following morning, Neko awakens to see that Kuroh has already prepared lunch. She takes a bite from a bento, and is thus chased by Kuroh for it. While avoiding him, Neko sees Yashiro being pulled away by a cleaning robot, causing her to attack the mechanism.
Neko later accompanies Yashiro to his classroom, albeit in her cat form. While he's writing out plans for his alibi, Neko picks up a red pen for him to use. Kuroh notices her and lets out a loud cry, startling Neko and causing her to transform back into her Human self. Embarrassed, she attempts to laugh it off.
During the lunch break, she happily eats the food Kuroh prepared for her before asking for more. She is offered extras by Kukuri, though she is disappointed to see that they only contain vegetables.
Afterwards, Neko goes with Yashiro and Kuroh to change into their Feudal Japan outfits. She is clueless about how to put hers on. As a result, Kuroh dresses Neko himself. While being dressed, she listens to Kuroh and Yashiro talk. She claims that she's always been with Yashiro since they first met, adding that he is good. Once she's been dressed, Kukuri checks on the three of them and compliments them on their looks. She states that Neko looks beautiful, which the latter agrees with.
She follows Yashiro, Kuroh and Kukuri across the campus to scavenge any information relating to December 7. However, Neko fails to be of any help to any one of them. Instead, she plays around with the cleaning robots or otherwise whines to be given food. When Yashiro goes to buy her a drink, he is revealed to have lied to Kuroh about how he enters the school campus, leading the latter to decide that he should be killed. Neko clutches onto Yashiro and tries to stop Kuroh from hurting him. She says that Yashiro is a "warm" person and proclaims her desire to continue having snacks with him. Yashiro pushes her behind him, and Neko takes the opportunity to hug him. Thankfully, Yashiro is spared from Kuroh's wrath after Kukuri reveals that he was on school campus on December 7–8. To this, Neko celebrates her feelings of relief with Yashiro.
Neko returns to Yashiro's homeroom with Kuroh and Kukuri. She is given rice crackers to eat, though is astonished to find that they are actually very spicy. Kukuri tells her that she will give out spicier rice crackers if she brings back Yashiro. Neko eagerly goes to Yashiro's room to complete her orders. She notices that Yashiro appears less cheerful than normal and asks whether he's having a stomachache, though Neko is told not to worry about him.
She takes his advice and brings him with her back to his classroom. Once there, Neko whines consistently for her rice crackers to be given to her. Though she does not receive her crackers, Neko is asked to go to the city with Yashiro and Kuroh, which she gladly agrees to do.
While in the city, she constantly whines about being hungry, aggravating Kuroh enough to stop at a restaurant to eat. Neko happily eats the grilled fish that they order and even tries to steal from Kuroh's tray. She is slapped aside though Yashiro gives her his fish anyway, making her cheer. While she continues eating, Neko notices Yashiro staring at a bulletin near them and wonders why. After they've eaten, all three head to a store nearby. Because Kuroh cannot read the list of items Kukuri sent them out to get specifically, he decides to call her instead. Neko whines not to and that they should go back to the school and ask her directly again. She starts crying and says that she hates telephones. When Kuroh asks why, Neko begins screaming and transforms into her cat form, darting away from the three.
As night falls, Neko finds her way to a soccer stadium that Yashiro and Kuroh have gone to. When members of the Scepter 4 force arrive to take them into custody, Neko uses her abilities to create an illusion for them, causing everyone in the vicinity to believe that they are in the streets of Shizume City during the day. Neko quickly reverts to her human form and leads Yashiro to an exit, with Kuroh following them. They are halted by the appearance of Lieutenant Awashima, and then the arrival of the Blue King. Neko returns to her cat form but is forcefully ejected from it due to the King's interference. Kuroh tells her to take Yashiro and leave immediately. Neko obeys his orders and runs off with her friend. However, they stop midway so that Yashiro can return to Kuroh and save him from the Blue King, albeit with Neko's illusive help.
Neko and Yashiro eventually regroup with Kuroh in a dark alley. Though scared, Neko receives praise for her actions at the stadium from Yashiro. It is then explained that she can manipulate memories in addition to creating illusions. Neko is asked to help Yashiro rediscover his past through her memory-altering ability. Though hesitant at first, she obliges. Through a film-like montage, she shows Yashiro her first memory of him, which was early on the 8th of December. Afterwards, she is asked to help him rediscover her memories from before; though initially unsure, Neko attempts to restore his memories from before, and manages to bring back a particular piece. However, when Yashiro expresses alarm at what he sees, Neko becomes worried.
The three head under the bridge to Ashinaka High School where Neko proclaims that they "made it back". When Kuroh becomes worried whether they made a good decision to do so, Neko says that it is fine, since it is their "home". She becomes happy when Yashiro pets her on the head and agrees with her statement.
She joins the two in the back of a delivery truck following Kuroh's attack on a Scepter 4 member. Neko waits while Yashiro speaks to Reisi Munakata on the phone. Afterwards, they relocate and hide themselves in a nearby ship. She states that she will do her best to lead them to the Scepter 4's location. Neko then asks what contraption Yashiro had made before leaving the delivery truck and is explained more about it. That night, she guides the two to a local airport and they hide near the runways, with Neko put as a lookout; after some time, using a pair of binoculars, she reports Scepter 4's arrival.
Yashiro, Kuroh and Neko later knock out a few Blue Clansmen before boarding their helicopter. They then depart from the airport with the other helicopters sent. During the ride to the Himmelreich, Neko expresses her boredom and decides to join the other two at the front of the aircraft. She becomes excited when another aircraft shines their light on them and begins pressing buttons, even after a warning from Kuroh to stop. When Yashiro and Kuroh talk about the other helicopters possibly interfering with their plan, Neko, thinking that they must be first to get to the Himmelreich, forcefully takes hold of the control stick and moves their aircraft towards the engine of the Himmelreich, unaware that they will be crashing into it. She maintains a cheerful and excited expression despite the others' worries and surprise. However, when the Himmelreich suddenly explodes, Neko, still unaware of their situation, simply looks on in awe at the flames. Soon afterwards, they crash, and are caught in a much larger explosion.
Luckily, they manage to survive and crash in a river in Shizume City while still remaining unscathed. A group of Blue Clansmen led by Seri Awashima approach their destroyed helicopter that following morning, but they fail to notice either of them, due to Neko's abilities.
Sometime later, they hear about HOMRA's takeover of Ashinaka High School and the three decide to head back. Neko helps them sneak past Scepter 4 on the bridge using her abilities again. By nighttime, they manage to make it back to Yashiro's dormitory and discover that it has been charred and torn apart. However, Neko is more fretful about her favorite food bowl being shattered. While Yashiro and Kuroh are busy discussing the situation, she attempts to fix her bowl, even telling the others that she is still busy fixing it when they try to leave. Neko ultimately decides to leave it as it is for the time being and says "goodbye" to the place, otherwise known as her "home".