Power

Power is childish, greedy, and almost entirely self-motivated. She tends to fight as if she has something to gain and is certain of her victory, and has no problems with running away from a fight where she is outmatched. She feels the need to boast her superiority over her fellow Devil Hunters due to her status as a Fiend. She has no loyalty to humans or Devils, openly admitting that she will join whichever is the winning side. Power also enjoys the thrill of a fight and enjoys showing off her strength and proving her own superiority. When she was in front of an swarm of zombies, she got excited and told Denji to watch carefully how she single-handedly defeats all of them. She is highly egotistical and often claims she is capable of doing things she cannot actually do, only to abandon them halfway through when the situation turns sour for her. She frequently deflects the consequences of her actions to those around her. Power is a compulsive habitual liar; after getting in trouble with Makima for killing a Devil when she wasn't supposed to, Power immediately blamed Denji and claimed he told her to kill it. She also blamed Denji for eating all of the emergency food that the team collected even while she had crumbs on her face, and when accused of abandoning a fight because she was scared, Power falsely stated that she ran away merely because she was hungry. Power is also rude, unkempt, and feels as though those around her should clean up after her. She self-admittedly rarely bathes or flushes the toilet and sees humans as being overly sensitive for caring about their hygiene so much. This may be because blood itself is seen as unhygienic, as other fiends aren't explicitly shown being unhygienic. Power has a tendency of imagining several ways of making humans kneel and suffer. When they were trapped in a hotel due to the ability of the Eternity Devil she spent most of the time there "planning" to win a Nobel Prize and become Japan's Prime Minister so she could raise up their taxes up to 100%. She has no problem gossiping and talking about her friends behind their backs; sharing the secret of Aki's shortened lifespan with the Angel Devil. Power sees no difference between pork, beef and human meat; being willing to eat all of them, even if the meat is disgusting zombie flesh. She hates vegetables, throwing them away when she finds them in her meal. Power is an insatiable glutton, eating all of the stored food that the team needed in order to survive the Eternity Devil's trap and hoarding food for herself at the Division 4's newbie welcoming party. When asked by Aki about what reward she could want as part of their mission, Power stated that she desired to suck a human's blood until they die. When promised Denji's blood, Power became ecstatic at the prospect. After returning from Hell and witnessing the power of the Darkness Devil, Power develops severe PTSD, being completely afraid of being alone and feeling that she will be swallowed by the Darkness Devil. As a result, she needs Aki and Denji to help take care of her, helping her to eat, bathe, and sleep, revealing a more vulnerable side. Though she is extremely selfish, Power was able to experience compassion for the first time towards her pet, after only caring about the smell and taste of blood and the feeling of death when she was killing something. This compassion prompted her to act for the sake of another being when her pet Meowy was kidnapped. Power also begins to care for a select few close friends, such as Denji, as evidenced by getting him a birthday cake, and later putting herself in direct danger in order to protect him. She also appears to care about Aki and is saddened and afraid when he becomes the Gun Fiend. Contrary to her core values, Power developed such extreme loyalty to her friend Denji that she denied her impulse to sacrifice him to Makima in order to save herself, ultimately saving his life at the cost of her own, and proving that she is capable of putting others before herself. After Pochita erases himself out of existence, thereby causing a new timeline to be created. Power is once again alive as a result, with her retaining most of her previous timeline's personality such as being bratty and a compulsive liar and quite boisterous and not being someone to abide by authority. She also doesn't seem to fear Nayuta as her superior or the fact that she is the control devil like she was with Makima. She doesn't seem to be a murderous back stabber like before and genuinely helps Denji by offering him blood in exchange for keeping him alive and being his "master" by making him her pet while also keeping the similar sibling like relationship as they had in the previous timeline. She also shares a loving relationship with her cat, Meowy and is jealous when she sees her cat loving Nayuta more than herself.

Fiend Form
Power possesses the corpse of an unknown woman or girl with long hair. She mainly appears being blonde. Her hair color varies from blonde to pink in manga illustrations, even appearing dirty blonde in some official art, and appears strawberry blonde in the anime. As a Fiend, she has red and yellow eyes that form a cross pattern, sharp teeth with defined fangs, and light red horns protruding from the top of her head. If Power accumulates too much blood, her horns become larger and more curved, and she can sprout additional pairs of horns from the sides of her head. Power usually wears the standard dress shirt, tie, and slacks required of Public Safety Devil Hunters. Normally, she wears breast pads to increase the size of her bust. She almost always wears her jacket hanging halfway off her body giving her an untidy, half-dressed appearance. In a new reality where Pochita never existed, Power wears her hair in pigtails while donning her jacket over her Public Safety Devil Hunter uniform as a Devil Hunter working under Nayuta's command.

In her original form as a Devil, Power claimed to be greatly feared to the point where other Devils would flee from her scent, though this is quite possibly just boasting. As a Devil, Power possesses all of the standard Devil abilities, such the ability to make contracts with humans for a price, restoring her health by consuming blood, take over a dead human body and their consciousness, becoming a Fiend, and reviving in Hell after being killed. Right now, Power has only one contract, being with Denji. In exchange for promising to find and befriend the reincarnated Blood Devil, Power gave Denji her blood. Denji used her blood to create a Blood Chainsaw and disturb Makima's regeneration.