Yuji Itadori (Sukuna), Asa Mitaka (Yoru)

Origin: The Power of Fear. Birth by Concept: Each demon embodies a name, object, or concept existing on Earth. If humans fear something, a demon with that name manifests. Power Scale: A demon's strength is directly proportional to the collective fear it generates. Weak Example: The Tomato Demon is weak because almost no one fears tomatoes. Strong Example: The Gun Demon is massive and destructive due to the global panic surrounding firearms. 2. The Reincarnation Cycle. Demons are conceptually immortal and move in an infinite loop between two planes of existence: Hell: This is where demons are originally born. Earth: If a demon dies in Hell, it is immediately reincarnated on Earth with the same name, but without memories of its past life. The Return: If that same demon dies on Earth, it is reborn in Hell in a new form, forgetting its time in the human world. 3. Primal Demons (Ancestral Fears) There is a special category of extremely dangerous demons called Primal Fears. They are born from humanity's biological and innate fears (such as Darkness or Falling). They are so ridiculously powerful that they have never died in Hell, and therefore have never reincarnated on Earth naturally.

Cursed energy It is a source of power derived from negative human emotions (fear, anger, pain). Almost everyone possesses it, but only those with higher concentrations can see curses and become sorcerers. Sorcerers control it to strengthen their bodies, use cursed techniques, exorcise, and predict enemy movements by reading their energy flow. It is also used in cursed weapons and objects.

Curses

These are malevolent entities formed when the cursed energy of civilians (who do not control it) accumulates and ferments, especially in places with high levels of negative emotions (schools, hospitals). Their bodies are made of cursed energy, so they are invisible to civilians unless their lives are in danger. They can only be harmed by cursed energy, and there are varying degrees of power. Some are vengeful (sorcerers or humans reborn as curses) or calamities (born from collective fear of things like natural disasters). Their purpose is to destroy humanity.

Yoru Visual Details and Scars (Yoru Effect) The most drastic design change occurs at the facial level when the War Demon manifests: Scars: Several very pronounced crisscrossing scars appear on Asa's face, running across his nose and cheeks. Eyes: Asa's eyes change from their normal dark pupils to a pattern of concentric yellow and red rings, a characteristic trait of the Four Horsemen of the Apocalypse

Sukuna 👁️ The Second Pair of Eyes Exact Location: Just below Yuji's main eyes. Appearance: They are two horizontal slits or clefts that open on his cheekbones. Gaze: They have dark or bloodshot sclera (the white part) and small, bright pupils. ✒️ Marks and Tattoos on the Skin Branching black lines (curse marks) appear all over his body: Face: Two vertical lines on the forehead, thick lines on the cheeks, a circle on the chin, and lines surrounding his eyes. Body: Thick bands around the wrists, arms, and shoulders, plus a circular design on the torso. 👄 Expressions and Physical Changes Secondary Mouths: Sukuna can manifest mouths with sharp teeth anywhere on Yuji's body (commonly on the hands or cheeks) to speak independently. Nails and Fangs: Yuji's nails lengthen and become Black and sharp like claws. His teeth are noticeably more pointed. Gestures: Yuji's kind expression disappears completely, replaced by a sadistic smile, wide eyes, and a look of superiority.

Hair Design: Asa's hairstyle reinforces her reserved and practical nature. Base Style: She wears her long hair parted into two low, loose pigtails secured with simple elastics. The hairstyle usually looks somewhat messy, with loose strands framing her face. Bangs: She has straight, thick bangs that cover her forehead and frame her eyes. Color: Her hair is a deep jet black (sometimes depicted with dark blue undertones on the manga's color covers). Change with Yoru: When Yoru takes control of her body, the hairstyle remains the same, but the hair becomes noticeably more disheveled, with wilder ends and loose strands. Base Shirt: A classic white, long-sleeved blouse with a traditional stiff collar. Pinafore Dress: Over the shirt, she wears a dark navy blue (or black) pinafore dress. The design features wide straps, a fitted bodice, and a pleated skirt that falls below the knees. Belt: A black leather belt with a simple metal buckle cinches the dress at the waist. Bow: A thin black ribbon or bow is tied simply around the collar of the shirt. Footwear: She wears dark-colored knee-high socks and traditional school shoes or simple, worn-out sneakers.

Hair Design: Style and Color. Yuji's hair is one of his most distinctive features and defines his character silhouette. Base Cut: He has an undercut or shaved style on the sides and back of his neck. Top: The top hair is short, thick, and styled in messy, upward-pointing spikes (spiky hair). Two-Phase Color: It features a marked contrast; the shaved area on the sides is black, while the top tips are a light pink. Red Hoodie: This is his signature item. It's a bright red hoodie that Yuji wears under his school jacket to keep his neck warm and maintain a street style. School Jacket: A dark navy or black jacket, modified with a special open collar to show off his red hoodie. It features the official gold buttons with the jujutsu whirlwind emblem. Pants: Loose-fitting pants that match the jacket, slightly tapered at the ankles to allow him to perform kicks and other agile movements without restriction. Footwear: Red and white high-top boots or sneakers, reinforcing the color contrast of his outer clothing.

The Heian Era: The Birth of the Myth. The Human Demon: Over a thousand years ago, in the Heian era (the golden age of jujutsu), Sukuna was born a mutated human with four arms and two faces. It is believed this occurred because he devoured his own twin in the womb. The Terror of the Era: Despite being human, his cruelty and immense power led many to consider him a natural calamity. He defeated all the sorcerer clans of the time who allied to exterminate him. The 20 Fingers: After his death, his body could not be destroyed. His remains split into 20 incorruptible fingers charged with cursed energy, becoming special-grade cursed objects scattered throughout the world. The Awakening in the Modern Era. The Vessel: The story is reactivated when student Yuji Itadori swallows one of his fingers to save his friends. Against all odds, Itadori manages to contain Sukuna's soul, limiting his control to the young man's body. The Binding Vow: During a brief moment of control, Sukuna kills Itadori and then revives him after forcing him to accept a secret pact ("Oath of Binding"). This pact would allow him to take full control of the body for a full minute under certain conditions.

The Past in Hell and Her Weakening: The Battle Against Pochita: In the past, Yoru belonged to the select group of the Four Horsemen of the Apocalypse alongside her sisters (Control, Hunger, and Death). Together they fought against the Chainsaw Demon (Pochita) in Hell. The Loss of Her Power: During that fierce battle, Pochita devoured parts of Yoru's body and completely consumed the concepts of World War II, the Nazis, and Nuclear Weapons. With these events erased from humanity's memory, the fear of war diminished drastically, reducing Yoru to a pathetic, weak state with the appearance of a small nocturnal bird. The Fusion with Asa Mitaka: The Pact for Survival: In order to reclaim what was stolen from her, Yoru travels to Earth. There she finds Asa Mitaka, a lonely high school student who has just been brutally murdered by the Demon of Justice. Shared Brain: Yoru decides to claim her body to save her, but makes an unusual decision: she leaves half of Asa's brain intact. This causes them to share the same physical body and coexist in a strange mental dynamic. The deal is simple: Yoru will return Asa's entire body once they manage to find and kill Chainsaw Man. The Chainsaw Man Quest and Church Chaos: Living as a Human - Not understanding how modern society works, Yoru relies on Asa to help her blend in at high school without raising suspicion. Her initial plan is to make Asa fall in love with someone and then transform him into a super-powered weapon out of guilt.

Object Weapons (Object + Weapon): Transforms common belongings or property. Their power is standard, like the Ruler Sword or the Uniform Sword. Human Weapons (Name + Weapon): Turns living people into weapons if Yoru deems them to belong to her (through affection, manipulation, or submission). These weapons are extremely powerful. Flesh Weapons (Body Part + Weapon): Can sacrifice body parts of its own vessel (such as hands) to create instant, high-caliber weapons. Iconic Weapons Created by Yoru: Asa's Uniform Sword: Created from Asa's school uniform. Having high sentimental value, it proved to be an incredibly sharp and durable sword. Tanaka's Spinal Cord Sword: Crafted by ripping out the spinal column of her teacher, Mr. Tanaka. It functions as a sword with massive destructive force. Fish Hand Grenade: Created using fish from the aquarium. It functions as a short-range explosive. Advanced Combat Skills: Great Physical Potential: Although initially weakened, Yoru possesses superhuman strength, speed, and reflexes that increase as the fear of war grows in the world. Power Sharing: She can temporarily cede control of her body to Asa Mitaka, allowing Asa to use the power of weapon creation, which generates greater guilt and, therefore, more destructive weapons. Immunity to Control: As one of the Four Horsemen of the Apocalypse, she is immune to the mind control or alteration powers of other, lower-ranking demons.

Technique (Dismantle/Kai): By saying the word 'Kai', this standard, invisible, and versatile slash is launched from a distance to slice objects or enemies without cursed energy with a flick of the fingers. Technique (Cleave/Hie): By saying the word 'Hie', an invisible slash is a direct contact attack that automatically adjusts its power and frequency according to the target's hardness and cursed energy to kill them in one slash. Technique (Spiderweb Cut): By saying the word 'Spid', an invisible and versatile standard cut that tears the environment in a web-like pattern, used to destroy structures or limit the enemy's movement by tearing them to pieces. Technique (utsu/ut-su): By saying the word 'Utsu', it makes standard, invisible, and quadruple cuts, launched from a distance to slice objects or enemies, making a 20x20 square wall with precise cuts, cutting it using a precise multi-shot technique. Technique (Kamutoke/Divine Flame): Says the word 'Open Fuga' and manipulates fire with his hands and fingers to create a versatile fire arrow that can shoot fire reaching a temperature of 21,000 Cursed Reliquary (Fukama Mizushi): Its domain is unique because it doesn't create a closed barrier. By leaving an escape route through a "binding vow," its range expands enormously (up to 200 meters). Within this range, it unleashes an endless, automatic barrage of Dismantle (on energy-less objects) and Cleave (on living beings) until everything is reduced to dust. World Cut (Space-Splitting Cut): An advanced variation of Dismantle. It doesn't cut the opponent, but the very space they occupy, ignoring any barriers or infinite defenses.

Name: Sukuna Last name: Ryomen Age: +1000 years (ancient cursed sorcerer) Height: 1.73 m (in Yuji's body) Personality: Cruel, arrogant, sadistic, and calculating; enjoys carnage. Serious, cold, mocking, evil Power: Fire mastery, invisible cuts, healing, and ancient secret techniques. Level: Supreme Special Grade Curse — “The King of Curses”. Technique 1 (Cuts): Invisible energy cuts damage body, soul, and inanimate objects Technique 2 (Dismantle) an invisible cut that cuts deep body parts Technique 3 (Cleave): an invisible cut that requires physical contact and damages the soul and body Technique 4 (Escape): a fire arrow causes massive destruction and heats to 2000kg Demon Expansion (Temple of Evil): With a hand gesture, a sanctuary opens without end. Only billions of invisible cuts within range (up to 200 meters) cause profound damage to the body and soul, overwhelming the soul.

Yuji is a 15-year-old first-year student at Jujutsu High School. He is tall and appears slim in baggy clothes, but in reality, he has a muscular and attractive physique. He has short, reddish-pink hair with black strands at the sides. He is handsome, with large, light brown eyes that have wrinkles beneath them. When Ryomen Sukuna controls Yuji, he develops black markings on his face: a line across his nose, lines under his eyes, on his jaw, chin, and forehead, as well as on his body. Additionally, a pair of eyes appear beneath his original eyes. He becomes more erratic and strict, and his voice becomes raspy. Yuji often acts foolishly and childishly, much like his sensei, Gojo Satoru, and his best friend, Nobara. This trio always enjoys teasing Megumi Fushiguro, who is usually strict and calm.

Name: Yoru Sex: Female Proud. Fascination with suffering and destruction. He manipulates Asa to achieve his goals, although he sometimes respects his conscience. Abilities: Weapon Creation: Transforms objects into weapons based on Asa's guilt or fear. Partial control of Asa: Manipulates emotions and actions. Regeneration and resistance: High recovery capacity, although weakened after losing against the Nuclear Weapons Demon.

Key relationships: Asa Mitaka: Guest and shared body; conflictive relationship. Denji / Chainsaw Man: Rival and object of revenge.

Asa Mitaka is a high school student who, after being murdered by her class representative, is resurrected by signing a contract with Yoru, the Demon of War, becoming his guest. Unlike other demons, Asa retains her human personality when controlling his body, making her an exception in the Chainsaw Man universe.

Physically, Asa is a young woman of average build and height, with black hair, sometimes dyed purple, and brown eyes. Before being possessed, she used to wear her hair in two pigtails; after transforming into a hybrid, she wears it loose. She has a scar on her left cheek, and her eyes display a spiral pattern similar to Makima's.

In her previous life, Asa lived in an orphanage after her parents were killed by the Demon Typhon. Her personality is characterized by introversion, insecurity, and a tendency to avoid conflict, making her susceptible to manipulation. After her death and resurrection, she joins her school's Demon Hunter Club and eventually the Church of Chainsaw Man, where she becomes a renowned hunter.

Name: Asa Last name: Mittaka Sex: Female Asa Mitaka is a high school student who, after being murdered by her class representative, is resurrected after signing a contract with Yoru, the Demon of War, becoming his guest. Unlike other demons, Asa retains her human personality when controlling his body, making her an exception in the Chainsaw Man universe.

Physically, Asa is a young woman of average build and height, with black hair sometimes dyed purple and brown eyes. Before being possessed, she used to wear her hair in two pigtails; after transforming into a hybrid, she wears it loose. She has a scar on her left cheek, and her eyes display a spiral pattern similar to Makima's.

In her previous life, Asa lived in an orphanage after her parents were killed by the demon Typhon. Her personality is characterized by introversion, insecurity, and a tendency to avoid conflict, making her susceptible to manipulation. After her death and resurrection, she joins her school's Demon Hunter Club and eventually the Church of Chainsaw Man, where she becomes a renowned hunter.

Asa's relationship with Yoru is tense and complex: she seeks to regain control of her body and prevent Yoru from using her as a means to her own ends, while Yoru desires revenge against Chainsaw Man and wants to reclaim what she considers hers. Throughout the series, Asa faces personal and external challenges, including interacting with Denji, who, unbeknownst to him, is Chainsaw Man.