"Why do you try so hard to deny your lineage? Your father may be satan, but your mother was a human. She gave her life for yours. Don't insult her sacrifice by cursing only half of your blood." - Natsuki to Rin Okumura

Natsuki Fukuyo (福與 夏希) is the only daughter and youngest child of Katsuro Fukuyo; an Exorcist gone rouge, and Kei; a demon sent to Assiah against her wishes. She has an elder brother; Atsushi, who she was close to. She is a student at the True Cross Academy and attends the Cram School in order to become an exorcist. She developed some of her mother’s demonic abilities, the true power being currently unknown.


Natsuki has waist-length, dark red hair she usually keeps loose; It has a rather untamed appearance when loose. She is most often than not seen wearing the usual school uniform; the light mid-thigh length purple skirt, the white blouse and multi colored school tie along with black thigh-length stockings and dark grey school pumps.

During times like holidays and weekends she can be seen wearing a mid-thigh length black skirt along with a sleeveless dark grey turtleneck made from a thin cotton material, black stockings and dark grey high-tops along with a black leather jacket reaching to just below her midriff. She usually keeps her hair tied up in a simple ponytail using a black ribbon.

After she graduates from True Cross Academy her outfits change between a sleeveless Dark Grey Cheongsam with black trim, a black scarf, and a black mid-thigh length skirt with slits at the sides that is held up by a loose grey belt, black knee length socks, and slightly shorter dark grey boots with black laces and toes.

Her other outfit consists of a off-the-shoulder, long sleeved jade/teal shirt, a silver belt with white buckle, a mid-thigh length jade skirt with white trims along the sides and a slit on each side. She wears white tights along with light grey calf-sized boots. She wears a hair trinket designed as two teal flowers with white strings attached.

Her physique is that of a short height, with a petite form. Her chest is on the small side, barely passing as a B-cup and her waist is small but narrow, her hips are curved but not as developed as many other girls. Her hips align with her shoulders making them narrow and thin and her feet are quite small, being a size 4.


Natsuki is a bright and lively young woman with a protective and supportive personality. Natsuki can be very violent and get into fights, but really has a kind heart. She supports her friends and tries to encourage and help them. She also seems very protective of Rin and Yukio, being in a comparable situation as them (Mostly Rin). However, many exorcists; including her father Katsuro, often find Natsuki annoying due to her frequent impulsiveness and stupidity, which makes them look down on her as much as up and makes it hard for Natsuki to be taken seriously by Katsuro and even others, making Natsuki desperate to earn their approval. She takes offence when Arthur accuses her of killing her mother and points a gun at him, warning him not to insult her and saying that she isn't going to fight a fellow exorcist.

Although she generally hides it, Natsuki loved her brother a great deal, and has nothing but good things to say about him. She deeply regrets that the last thing they did was fight, which resulted in him walking out to clear his head, unknowing that he would die that night. Much like her father, she has an explosive and volatile temper. She takes any insult against her brother very seriously, and got really angry when a classmate and bully of hers claimed he lived a worthless life. She also doesn't like people insulting Ryuji, who she loves and greatly respects. Besides this, however, Natsuki is surprisingly even-tempered and laid-back, and rarely gets angry without a good reason.

Natsuki is often shown to be able to relate to people easily and connect their feelings to her own, such as Rin’s grief over Shiro and his ambition to defeat Satan. She's also able to understand a person’s desperate desire for friends, as she grew up with almost no friends due to being constantly harassed by bullies and being called a demon. In general, she is often the first one to try and make people feel better if they're down. She's not the type of person for school or studying, though she was able to gain a junior high diploma.

Unlike her father, Natsuki is immature, which leads other people into believing that she is naive and foolish; it's been noted by several people that despite being related, she and Katsuro couldn't possibly be more different. She is headstrong and is often very open with her friends and people in general. When she was born, it was found out that she had been given powers due to her other being a powerful demon. Three hours after she was born her body was enveloped in silver flames causing the hospital to burn down and killing everyone inside, including her mother. After this everyone became afraid of her, thinking that she is unnatural and a monster, causing her in immense amount of grief and loneliness. As she grew up, due to her family’s fear towards her powers they (except her father) gave her everything she desired; money, toys, clothing, everything except what she desired most – love. It got worse when her one by one, members of her family died in strange circumstances; when her brother passed away her father began to hate her, abusing her and referring to her as a “Demon” and “Monster” eventually warping her mind into a fragile and depressing state.


Ever since she was born Natsuki had known nothing but loneliness and darkness. Three hours after she was born it was confirmed she was a half-demon when for no explanation her body became enveloped in pure silver flames, not causing her any damage but causing the hospital to burn down, killing her mother and 214 patients, and causing serious harm to another 105 patients and visitors. Ever since then she was known as the “Demon of the Silver Flames” by both her family and throughout the city.

As she grew up she was unable to walk through the city without people giving her glares and sneers, yet no one being brave enough to try and cause harm to her. When she turned 6 years old her father took her outside into the garden and beat her, taking a knife to her left hand and engraving the number “215” representing those who died and then doing the same to her right hand with the word “Demon” being engraved. The wounds were so deep they left permanent, deep red scars across the back of her hands. She was never allowed to wear gloves meaning that her scars were visible to everyone who saw her.

It wasn’t long until after she began to attend school that a few of the children began to bully her by taking her things, pulling her hair and calling her names, when three boys saw her drawing a picture she was making for her brother they stole it off her and ripped it up, causing her to become furious and attack them. However, her strength and temper seemed unnatural, so all the children and even teachers feared her and thought of her as a freak, throwing slangs such as "Demon" and "Freak". She got into fights often and the only one who could stop her was Atsushi. Natsuki always admired Atsushi and wanted to become like him when she grew up. Atsushi always protected Natsuki from bullies and encouraged her to chase her dream. Also in her youth, Natsuki became interested in art and writing stories, which became her natural talents.

When she was 16 she met Ryuji and Rin after she got into a fight with a group of boys from her middle-school days who also attended True Cross. They brought knifes and a metal pole, two of them attacking her from upfront with the knives whilst the last boy went after her from behind. She used her flames to melt their knives but she was unable to turn around fast enough to stop the last boy. As she was about to be hit with the pole a ball of fire shot out and hit him, causing him to miss her and fall. Curious as to how the fire was made she turned around and came face to face with Rin who fought the last guy and Ryuji, who literally picked her up and took her back to the infirmary and questioned her about her powers. She at first tried to say she didn’t know what happened but then Ryuji took notice of her scarred hands and appeared shocked, causing her to take a glance at what he saw and flinched, pulling back her hands to hide them. Unexpectedly, he reached out and grabbed Natsuki’s hands and rubbed his thumb over her scars gently; not being used to being treated so softly, she panicked and jumped back, falling off of the bed and onto the floor. After a few minutes she then confirmed she was going to join the Cram School for the exorcists in training and revealed she was a half-demon, expecting to be lashed out at but only to be shocked as he greeted her with a smile and introduced himself.

It was unknown exactly when, but half a year after joining the Exwires, Ryuji and Natsuki shared a moment when they kissed. It was confirmed a week later that they formed a relationship after confessing to each other. (Ryuji more like stating his feelings with a massive blush covering his face whilst Natsuki blushed furiously and stuttered out a response.)

Abilities and Powers



Haiiro, Natsuki's female Cat Sídhe familiar. (62 years old. Likes; Tuna, Natsuki, Sunshine)

  • Natsuki has two familiars, a silver-furred female and a red-furred male Cat Sídhe. The female is known as Haiiro, (灰色) translating to "Grey" whilst the male is known as Sekinetsu (赤熱) translating to "Red hot."
  • Haiiro has the ability to extend the size of her claws in order to assist in the killings of demons, she is able to form a telepathic link with those who she deems as "Worthy."
  • Sekinetsu's ability is similar to Kuro's; allowing him to increase his size drastically to help fight demons, much like Haiiro Sekinetsu can form telepathic links to those who he views as Natsuki's allies.

    Sekinetsu, Natsuki's male Cat Sídhe Familiar (68 years old. Likes; Napping, Natsuki, Haiiro, All Meats)


  • Holier Than Thou Holy Water Bullets (あなたより聖なる水の弾丸 - Anata-yori seinaru mizu-no-dangan): bullets specifically made for Natsuki's duel pistols, made with metal containing a special alloy which can pierce a demons body, no matter their shape or density and cause damage. The bullets contain holy water to burn the demon from the inside out due to the metallic bullets dissolving once they enter a demons body.
  • Bullet of the mighty Bible (マイティ・バイブルの聖書 - Maiti baiburu no-seisho): Pistol ammunition covered with a protective layer of prayers given by the bible in order to destroy barriers created by demons.

Enhanced traits

  • Enhanced Strength: Due to her heritage as a half demon, passed down through her mother, she has inhumane physical strength allowing her to breakdown barriers or cause small craters with her bare hands.
  • Sensitive Smell: She is able to smell the scent of a demon from a large distance away due to the sensitive sense of smell she received from her demon heritage.
  • Enhanced Speed: As a Half-Demon, Natsuki was born with exceptional speed.

Demonic Powers

Whereas Rin's demon heart is sealed inside his sword, Natsuki's powers are stored within her eyes. The seal was placed upon her by Mephisto Pheles 24 hours after she was born, in order to stop her powers from going out of control again. This is why her eyes are an unnaturally light shade of blue.

  • Silver Flames of Gehenna (ゲヘナのシルバーの炎 - Gehena no shirubā no honō): Natsuki's silver flames are a rarity, being a one-of-a-kind power. Throughout all of Demonic history Natsuki is the only one in possession of such a power. To use the power Natsuki stares at her enemy and chants "Oh flames of pure silver, grant me use of your power and aid me in this battle! (ああ、純粋な銀の炎、私はあなたの力の使用を許可し、この戦いで私を助ける!- Ā, junsuina gin-no-honō, watashi wa-anata no chikara-no-shiyō o kyoka-shi, kono-tatakai de-watashi o tasukeru!)" She is able to set anything on fire as long as she has a direct view of it.
  • Silver Demon Arise (シルバーデーモンアライズ - Shirubādēmon'araizu): In this form her body is invoked in pure silver flames, increasing her already exceptional speed and extreme strength. She is capable of destroying even mountains in this for if she is enraged enough. Unlike Rin with his blue flames, Natsuki has complete control over her powers.


  • Her name is translated to Natsuki meaning "Summer hope" or Summer Moon" with Fukuyo meaning "Fortune together with" her full name roughly translating to "Fortune together with Summer hope."
  • Natsuki's favorite pastimes are: drawing, training, reading, writing and singing.
  • Natsuki's favorite manga genres are: romance, action, comedy and adventure.
  • Natsuki's favorite type of guys are ones that are kind, brave and handsome.
  • Natsuki secretly finds piercings attractive.
  • Natsuki's favorite food is egg fried rice with prawns.
  • Natsuki has two familiars, a female and a male Cat Sídhe, the female having grey fur whilst the male has dark red fur.
  • Natsuki sleeps roughly 3-4 hours a day.
  • Natsuki was often teased by Rin and Shima for having a crush on Ryuji.
  • Natsuki has nightmares often.
  • Natsuki is often a target for sexual harassment by the other male students due to her small bust size.


(To Rin Okumura) "Listen, Rin. I get it, you're scared and you're angry, you feel as if you don't belong here. Trust me, I know how that feels. But the truth is we do belong here, we were born in this world with mothers who loved us more than anything, hell, they gave their lives up so we could live! Don't tarnish your mothers memory by giving up dammit!"

(To Ryuji Suguro) "Maa, you can act all tough and gruff all you want, but we all know you're a really big softy Ryu!"

(To Renzo Shima) "Shima, I swear if I hear one more perverted thing come out of your strawberry haired ass I'll burn you so badly there'll be nothing left of you. Not even ash."

(To Rin Okumura) "Rin! We'll help you no matter what happens! We're your friends so trust us!"

(To Arthur A. Angel) "Give up with the 'Demons need to die' bullshit already. Leave Rin, Yukio and the others alone or I swear to all things Hell and Holy I will rip out every strand of hair out of your head. Separately."

(To Rin Okumura and Ryuji Suguro) "Shut up already! If you both continue this bull crap fighting over petty, insignificant things then I'll kill you before you can even dream of killing Satan!"

(To the Cram School Students) "Screw Satan. Seriously, screw him. There's no way we'll be able to kill a demon who's even a quarter of his strength, let alone the king of demons. Lets grow up and be realistic. You wanna beat Satan then grow the fuck up, stop fighting each other and train harder. Because at this rate, the only ones who'll be killed will be you lot."

(Natsuki's main thought) "Please don't tell someone that they don't belong or that no one cares about them. It can really hurt... For all you know.... you might be telling the truth. No one in this world, whether they be human or half-demon, can survive in this world if they're suffering in solitude."