Yoru

Yoru is the War Devil who embodies the fear of war. She is a member of the Four Horsemen, who now occupies Asa Mitaka's body as a Fiend.Following her taking over Mitaka's body, Yoru sets out to locate Chainsaw Man, whom secretly attends the Fourth East High School with them

Yoru is first shown to be very confident and prideful, treating her opponents as mere warm-ups and confidently vowing to take back nuclear weapons from Chainsaw Man. This might be a sign of her over-confidence as she lost to him previously while at full strength and is significantly weaker now. However she is aware of her limitations and will back down from a fight if she believes the odds are against her. Yoru holds little sentimental value or attachments to humans, and is mostly uncaring of Mitaka's feelings, as evidenced by her blatant disregard for Mitaka's feeling of friendship for Yuko, repeatedly asking Mitaka to kill Yuko to use as a weapon or when she goes as far as to physically hurt Asa herself to forcefully regain control albeit with the intention of saving them both. She's been shown to be very cold and logical which clashes with Asa's highly emotional personality. Since she's completely unaffected by the Falling Devil, that means she easily gets over highly traumatic events such as being almost killed by Pochita and losing her power. Due to her predisposed nature as the War Devil, she keeps getting into conflicts with everyone around her, sometimes intentionally and sometimes not. Ironically these conflicts usually serve to hurt her. Later, Yoru devastates a whole city while using her powers and laughs maniacally when looking at the destruction she caused, reminding Asa that she, at her core, is still a devilUnlike her fellow Horsemen Makima and Fami, who are almost always calm and composed, Yoru is more "human" as in flawed, immature and naïve. She is prone to losing her temper, and became embarrassed and angry at being rescued unintentionally by her archenemy, Chainsaw Man. In her anger, she sometimes throws childish tantrums by punching and screaming into the pillows on Asa's bed. She is very insecure and gets royally offended whenever her strength or intellect is questioned. Yoru is also worried about losing her power and being forgotten, showing a more sensitive side. Adding to that, she seems to show signs of sympathy, at least towards Asa. Yoru is able to form emotional attachments to others, such as her "comrades" whom she wants to rescue from Pochita's stomach, and the Gun and Tank Devils whom she considers her children and is hesitant to turn into weapons, even if she eventually does so. She does not have a good understanding of human society or relationships and takes things at face value, is easy to provoke and often threatens Mitaka with death. Though over time she grows closer to her and seems to understand and adapt to human society more, albeit she's still quite inept and will often unintentionally worsen her relationship with Asa because of that. Despite her apparent social-ineptitude she is very cunning in dangerous situations such as when fighting Devils and is easily able to keep a cool head unlike Asa. Though in the most extreme of circumstances Yoru will panic and scream out in fright, such as when Asa was caught by the Falling Devil

As Yoru has grown more and more powerful, her relationship with Asa has only strained further, and as of such, she's increasingly shown to disregard her host's emotions. One such example is how despite being aware of her traumatic experiences with controlling parental figures, Yoru still justifies transforming her "children" into weapons by telling her that a child is merely their parents' property. Another is how Yoru didn't take Asa's feelings into consideration when she shared an intimate moment with Denji; something which made her mad enough to be able to force the War Devil to hurt herself in retaliation, which surprised Yoru who said she was acting on Asa's feelings at the time. When Yoru finally reveals herself to Denji as "Asa's other personality", she jokes about how Asa is on the verge of a mental breakdown over all the lives she's killed in her rampage against Chainsaw Man, and still continues killing some more people. Despite the incredibly manipulative and toxic nature of their partnership, Yoru is the closest thing Asa has to a friend

Yoru resurrected and inhabits Asa's body, turning her into the War Fiend, but left half of Asa's brain intact, keeping Asa alive. With the two now sharing one body, Yoru was originally planning to use Mitaka as a way to blend into human society as she's unfamiliar with it. At first she is very hostile, threatening to kill Mitaka if she doesn't cooperate. However, she did not go through with her threat of killing Mitaka when Mitaka refused to go into school, and despite making such threats several more times through the story all of them seemed to be no more than saber rattling without any real weight behind them. Yoru is tolerant of Asa's antics, frequently compromising with her and has offered to do favors for Mitaka, such as "take care of" the kids who were bullying her and provided the easier name of "Yoru" when Mitaka complained that "War Devil" was too difficult to use as a name. Her vendetta against Chainsaw Man means that she will tolerate anything so long as her goal is ultimately still being worked towards.After their fight with Yuko, Yoru's perception of Asa changes, no longer viewing her simply as a means to blend-in but realizing that Asa is extremely good at making strong weapons. Because of this, Yoru views Asa as indispensable as she cannot defeat Chainsaw Man without her help. Hinting at this is the fact that she told Asa to "stay back" after encountering the Falling Devil suggesting she might have took over not only with the intent to protect herself but also Asa specifically. Another example is when Yoru didn't take over the rest of Asa's brain even while Mitaka is actively putting both of them in grave danger. Yoru has created her mental image of Asa's personality; Her mental image of Asa is fairly flawed as Yoru deeply miscalculates Asa's behaviour in a life-or-death situation, being very confused when Asa gets scared and mad at Yoru for cutting her hand.Over time Asa grew used to Yoru's presence to the point of trying to chat with her having forgotten that they're currently separated. However despite growing used to Yoru's presence she's still not fully comfortable with her and doesn't trust her one bit. Yoru on the other hand, being a Devil, still doesn't understand Asa and gets frustrated at her perceived irrational behaviour, it's likely she doesn't understand the concept of depression and assumes Asa's sadness came entirely from the influence of the Falling Devil.In tense moments Yoru, particularly if Asa's fright is preventing her from taking control, will go to cruel measures to save themselves such as self-harm. Though her cruel measures don't seem to be done out of malice but purely out of a logical and survivalist mentality. Asa does not appreciate this at all however. Yoru was confused and angry at Asa's emotional response to this as she thought she was only trying to help her. Either due to her lack of humanity or a misunderstanding of Asa's character she continues trying to convince Asa using cold and logical arguments despite the latter being emotionally distressed. Ignoring Yoru's unsupportive comments she grows frustrated that Yoru still doesn't understand her feelings despite being able to read her mind and continues to break down in front of her perhaps seeing comfort which Yoru unfortunately still does not provideYoru will occasionally mention when she thinks Asa is being too self-deprecating and will half heartedly try to comfort her which could be signs of genuine sympathy. However, Yoru could simply be putting on a mask to make Asa more likely to continue cooperating with her. Yoru still values her own goals greatly over Asa's feelings as shown by her deciding to kill Yuko despite Asa's protest or trying to turn Denji into a weapon after Asa falls in love with him. She has also been shown to be manipulative towards Asa, such as trying to gaslight her into killing Yuko or morally justifying murder as a "necessary evil"

Yoru and Asa decided Denji would be their target to be turned into a weapon. Despite not getting involved directly Yoru will push Asa to continue her date with him even if things don't go her way. She views him as a punk and is annoyed at her feelings of affection for him due to sharing Asa's brain. However her feelings for him were initially very shallow as she immediately tries using these feelings to turn him into a weapon, albeit unsuccessfullyLater during his movie date with Asa, she tries to push him away presumably to keep him safe from Yoru. In response she takes over and kisses Denji likely in hopes of quickly winning his heart which would allow her to finally turn him into a weapon, but she is swiftly incapacitated by Nayuta instead. After kissing him, she could be seen visibly blushing. After their memories have been wiped and altered she assumes Denji stood them up but is indifferent to it and swiftly suggests they target a different boy instead. This is in stark contrast with Asa's reaction who was deeply hurt. This love-hate relationship with Denji continued, with the most evident being Yoru pleasuring him in the alleyway after she regained her memories of the kiss. Although it eluded her for a while, Denji is her fabled arch-nemesis Chainsaw Man, who she hopes to defeat in order to regain Nuclear Weapons and get revenge. She despises him for defeating and weakening her which caused wars to cease and in turn reduced her to a shadow of her former self. Furthermore, the fear of war became so minute that she was afraid that she'd fade out of existence. She hates him to the point where she had a meltdown after she's unintentionally saved by him from the Bat Devil. To her dismay the situation repeats itself as they are saved by him once more during the Falling Devil fight, after which Asa falls in love with Chainsaw Man, much to Yoru's protests. Her desire to defeat the Chainsaw Devil, however, has unfortunately consumed her; even though she acknowledges that transforming the Gun and Tank Devils - two devils that she considers to be her own children - into weapons would completely invalidate her goals of freeing her comrades, she does so just so she can have the chance of defeating her nemesis and prove that she is better. When trapped in the Aging Devil's world, Yoru once again tearfully kisses Denji who himself is crying. When he pushes her off and asks her why she did that, she coyly replies she finds him "cute" when he cries. Upon escaping the Aging Devil's world, Denji asks Asa how she got her arms back and what's going on with her, Yoru finally reveals the truth, calling herself "Asa's other personality". Yoru and Denji run off to a restaurant. When Denji asks her if she likes him, Yoru says Asa likes him and since they share a brain she does too, and offers to have sex with him but gives him an ultimatum: she'll have sex with him only if he can defeat the Death Devil, or else she will turn him into a weapon and do it herself

As a Fiend, Yoru can not make contracts. However, she still has all the other standard Devil abilities, such as reviving in Hell after being killed, restoring her health by consuming blood, fear empowerment and enhanced physical prowess. Despite being rather weak at the start, Yoru has the potential to become one of the strongest Horsemen, even strong enough to prevent the upcoming apocalypse. Currently, Yoru has taken possession of Asa Mitaka's body, after her head got sliced in half by the Class President. The War Devil, however, only took over half of her brain, leaving Mitaka’s consciousness intact while still being able to take control over Mitaka’s body anytime she wants to unless Asa is stricken with fear. Adding to that if Yoru is already in control but Asa get's frightened she'll lose control. Thanks to this unusual circumstance Yoru is able to feel human emotions despite being a Devil. Whoever isn’t in control of the body will appear as a hallucination to the other and can even communicate to them. Supernatural Abilities:Although part of the Four Horsemen, Yoru claims that her Devil power weakened after her body was partially devoured by Chainsaw Man. This, combined with the long absence of wars in the human world, has greatly diminished her original strength. Adding to that her strength was reduced even further by becoming a Fiend. Combining all of these factors her current strength is a mere fraction of her full power and is by far the weakest horsemen.During the events of Chainsaw Man Church arc, Yoru experienced a significant power boost due to the fear of war rapidly rising

Enhanced Speed: Yoru is able to move very quickly, easily jumping around and dodging attacks from the contracted Class President and Yuko's Devil form. As the public starts to fear war again, Yoru's speed exceeds the infamous speed of Quanxi; she moves so fast that Yoshida, who was able to keep up with Quanxi, has a delayed reaction

Enhanced Strength: Yoru was able to pull Tanaka's head off his shoulders and spinal cord out of his body, requiring a great deal of force, and is able to easily carry objects as big as herself with one arm over her head. Her strength significantly increased after she experienced a tremendous power boost from the increasing fear of war

Enhanced Durability: Yoru is able to take hits that would kill an ordinary person, such as during her battle with Yuko she took a serious hit that flung her across a classroom and into a wall, but was able to get up moments later without any injuries. Later, Yoru's durability increases even further; Yoshida's sword, which was previously able to cut off her arm, could only make a minor skin-deep cutYoru has the power to transform anything she owns into a weapon, whether it be an object or a living being. Initially, to activate the weapon transformation, Yoru had to touch what belongs to her and say the name of the weapon, but as her power increased, she and Asa became able to create a weapon without even touching the related object and telekinetically summon them regardless of distance without even calling their names verbally. The strength of the weapon is proportional to the amount of guilt Yoru and/or Asa feel in creating said weapon. There is no objective measure of when something belongs to Asa or Yoru, but the greater the guilt, the more powerful the weapon will be. So far the only types of weapons that were created have been either melee weapons, such as swords and spears, or explosives such as hand grenades. It is unknown whether Yoru can create more advanced weapons.

Flesh Weapon Creation: Yoru is able to make anyone she "owns", including humans, Devils and Fiends, into a variety of deadly weapons almost instantaneously simply by touching them. This does not appear to immediately kill the human, as they can still scream in agony. In order to make a flesh weapon, Yoru must either: take a limb from the victim which she can then turn into a weapon, kill them and turn their remains into weapons, or form a relationship with someone where in they "belong to her". She can also make weapons from her own body parts which will violently tear themselves off her if she does so

Left Tank Gauntlet: a tank-themed arm gauntlet formed from the Tank Devil after it arrived to help Yoru fight back against the rampaging Chainsaw Devil. Yoru is capable of firing off bullets using the gauntlet

Right Gun Gauntlet: A gun-themed arm gauntlet formed from the Gun Devil during Yoru's rematch against the rampaging Chainsaw Devil. Like with the Left Tank Gauntlet, Yoru can fire bullets that are strong enough to pierce through the Chainsaw Devil's body and tear off some of his arms

Appearance: After taking over Asa's body and occupying half of her brain, the War Devil took on her appearance, but with added facial scars across her the center of her face and left cheek, which are in the same location where Mitaka's face was slashed by the Class President. When Yoru takes over, her eyes have multiple rings, similar to Makima, who was her sister and another Horseman. Her hair is also usually worn loose rather than in twin tails like Mitaka, and her posture is a little more straightened and confident in comparison to the timid and shy Asa

She has brown eyes that are usually pitch dark, though the irises become much brighter in some situations. Her hair is black and is sometimes colored with a brown tint. The hair reaches the middle of her back, and she wears it in two low twin tails, making it appear shorter. In the past, Asa wore her hair at shoulder length. After the events of the Chainsaw Man Church arc, Asa lost her right arm following her fight with Yoshida, and later her remaining arm during her fight with Pochita.This leads to Yoru sacrificing the Tank and Gun Devils to regain their arms while using them as weapons/gauntlets.She wears her female uniform which consists of a long-sleeved button up shirt worn beneath a pinafore style dress with a pleated skirt that extends below the knee, a bow at the collar, a wide belt at the waist, and black, knee-high socks. She also wears sneakers. After freeing Denji from the facility, she is seen wearing a baggy top with a t-shirt underneath and black pants. Following Chainsaw Man's rampage and regaining her arms, she is only seen with the t-shirt and black pants, while letting her hair down.