Author Note: This is my first try at writing a story heavily involving Japan Mythology, mostly Yokai. I'm not well versed in Yokai lore, which I most take from two arguably trusted Yokai wiki and Yokai dot com, and old Japanese culture so I will accept all criticism about them. Furthermore, the protagonist's Yokai power is similar to that of Nioh 2's Hideyoshi but with the advantage of freely transforming at will but not as strong as in the 'Yokai zone'. My OC isn't a half Yokai at born; he is partially turned into a Yokai to save his life.

Being a DxD story, it is bound to have harems so yeah, a harem for the protagonist it is. The members are, for now, Yasaka, an immortal Yuki-Onna named Kaede, who is originally a Tsurara-Onna, the reincarnated Kiyo-Hime and Princess Inaruna from Shin Megami Tensei Devil Summoner. I will add more when the story reaches the appropriate arc.

Due to the increased activities of foreign demons, the Yokais had been harassing and killing the people to the point Meido was starting to be overcrowded. Also, there was a rumor in Jigoku that the slumbering 'King of Fantasy' was gathering the negative energy from the human world and this agitated the imprisoned Onis and Onryous.

Enma-Daioh and his associates couldn't contain this anymore and they needed a solution. One of his attendants, Shimyou, suggested finding a 'hunter' to repel the invading elements but the rest disagreed. Per the contract with the First Emperor Jimmu, no infernal being was able to walk on the mortal plane without the permission of Tengoku, even if it's Enma Daioh himself. The ruler of Hell sighed; the troubles with Shinto pantheon hadn't been resolved completely yet and now, another big one arose.

A tear of dimension appeared in the middle of the hall, surprising all attending. A katana with a completely red edge was omitted out of it along with a blood-stained paper wrapped around the handle. The sword impaled the ground before the tear disappeared. Enma's close attendant, Ono no Takamura, carefully approached the objects. When he gripped on the sword, he suddenly got overwhelmed by a massive bloodlust aura that if it hadn't been for Enma's intervention, he would have been consumed by it.

"Maken...Muramasa!" Shiroku exclaimed in astonishment and fear. The infamous sword had absorbed so much blood, hatred and demonic essence that it developed a sort of sentient and nothing could wield it without harnessing its hunger, even Gods.

"Are you well, Takamura?"

"I'm…fine, Enma-sama."

Chanting madou, the attendant went to remove the torn paper from the sword and handed it over Enma. The king of hell opened and examined the content; there was only a short phrase.

Fujiwara no Gekkoutane

A bastard son of the current regent Fujiwara, Gekkoutane was abandoned by his father immediately after his birth. His mother, a beautiful daughter to a farmer near the Imperial Capital, was raped by the regent when he was passing the village. Gekkoutane's childhood, despite the cruel sayings from the neighbors and Fujiwara concubines, was relatively peaceful. He was gifted with the Judge Eyes, allowing him to perceive a person's hidden side with a glance. Therefore, he was able to protect his mother from the potential assassins from the Fujiwara clan by alarming the local troops many times.

Gekkoutane lost his mother during the Yokai Scourge at the hands of a Reiki and his entire village was wiped out. He began his life as a street kid for a long time. During that period, he had to fend off wild animals, cruel adults and fellow street children many times that eventually he developed his own self-defense fighting style. Gekkoutane usually sneaked around the school areas and eavesdropped the lessons so he was regarded as a very bright 'street rat' by a lot of people.

During a night, he rescued a logger from a Kappa and was allowed to stay in the logger's house as a reward. The life with the logger was smooth until he was nineteen, the age many youngsters began to love. Gekkoutane soon desired a woman of his life but his previous status as a street rat caused many girls to stay away from him except one.

In a heavy snowstorm evening, a female traveler named Kaede took refuge of their house. He noticed that, under some kind of sorcery, he started to be attracted to Kaede and perhaps, she to him. She kept acting lovey dovey to him that the logger suggested they getting married. They did a small ceremony and the logger was kind enough to build a small but very comfortable house for them. They lived together for two months when she suddenly disappeared. Gekkoutane went around to search for her until he saw her getting intimate with the logger and the last shred of emotions inside him was erased.

Gekkoutane regained enough control to go to the local temple and asked the monks for help. They explained that she was a Yokai and was either a Yuki-Onna or a Tsururu-Onna due to the circumstances of her introduction. The young man asked for an exorcism of whatever curse he was under and he was granted, along with a talisman to banish the female Yokai if things got rowdy. On his way back to his house, he was conflicted at the head monk's words: he suspected Kaede was a Tsururu-Onna, born from Gekkoutane's loneliness and desire. She was created to be his wife, his significant other half yet she betrayed him.

As expected, Kaede was gone when the spring came and the logger was shocked at Gekkoutane's cold but accusing declaration before being killed by a clean cut at his throat. Gekkoutane left the dead man's house and vowed to never believe anyone again. He lived in solitude on the mountain and rarely went to the village. Soon, winter came and unsurprisingly so did Kaede. The yokai dared to knock his door and greeted him like a wife returning from a workday. He didn't say anything and went to pick up his sword and the talisman.

"D-Dear, what are you doing –"

"Silence, cur." His voice was filled with coldness and tranquil fury. He brought the sword up and attacked her, forcing Kaede to call out an icicle naginata to defend herself. "So, you have shown your true color. A disgusting monster aiming for my life force. I shouldn't have killed Ootani. He was just one of your victims."

"What are you saying, Dear?!"

"No longer can your lies taint my mind, cur." Despite his determination to kill her, his Eyes declared that she did not come back to kill him and she genuinely loved him as it was her nature. But too late for her, Gekkoutane had closed his heart shut. He kicked her at her chest, pushing her backward, and advanced for a thrust. Before she could raise her weapon in response, he slapped the talisman into her body, forcing her to cry in pain and soon her human figure reduced her original form: a woman with inhumanly white skin and blue irises in a kimono made of ice.

As part of the exorcism, he was granted a small ability to vanquish yokais that was implanted into his eyes and his sword. He was about to go for the kill when his heart skipped a beat. A rush of fond memories between him and Kaede resurfaced in his mind.

"Krk…"

Tears began to flow on his face as Gekkoutane kept raising his sword but couldn't find the strength to do so. He threw the sword away in anger and glared at her for a moment before turning back. "Leave and don't you dare show your face in front of me again."

"Dear…"

"Leave! I will not hesitate next time."

From that day, Gekkoutane trained himself to become a Yokai Hunter. He was famed for his brutal efficiency at killing monsters and assisting the Onmyoujis in exorcising Yureis and Onryous, the latter always forced him to use his power to stop them from harming his clients. He soon made his name as the Fearsome Moonlight.

To the yokais, he was both feared and respected as he only hunted down evil Yokais and left out the harmless, helped them even. A notable example for this was during the reign of Emperor Gitei, he had fallen ill severely and Abe no Yasunari found out that his favorite concubine, lady Tamamo, was a kitsune feeding on the Emperor's life force. The regents immediately ordered troops to pursue her. She was badly wounded when she came across Fujiwara no Gekkoutane at the riverbed.

"A kitsune…" He spoke out while examining the yokai with the Judge Eyes. "A nine-tailed one to boost."

"Ah, it's over…" Tamamo lamented and wished that she should have stayed back there. At least dying at the hands of the Onmyouji was more peaceful than those of the Moonlight. Behind her, the samurais arrived at the scene and they looked relieved to see her at his mercy. They seemed to expect him to slay her in the spot.

"You are hurt."

"A fitting end for a yokai like me…" Tamamo said with a sad smile. Gekkoutane's eyes darted around and drew a dagger. The kitsune thought her time was up when the Hunter deflected an arrow. The warriors were alarmed and went to search for the assailant. He raised a hand.

"I believe you are pursuing the one harming the Emperor, correct?"

"Aye. The Onmyoji Abe no Yasunaru found out that she was sucking off his Highness' life and expelled her."

"I see. Then you are following the wrong person." He put away the dagger and produced a small bottle with green liquid from his bag before giving It to Tamamo. Gekkoutane turned to the leader of the samurais. "Go tell the Onmyoji that I require his assistance for the exorcism. Bring along what you perceive as the Emperor's second most favorite concubine."

"Understood. But sir, the last part is confusing me."

"You will understand in time. Go, before the true culprit escapes."

The samurai departed right away. Tamamo looked at Gekkoutane with hope in her eyes.

"W-Why?"

"One: once a kitsune achieves all nine tails, she won't require life force to exist anymore as she is now virtually immortal. Two," He came down on her level and stared her straight in the eyes. "Do you recognize these?"

"The…The Judge Eyes?!"

"Indeed. I have seen your thoughts and memories. You must be loving Emperor Gitei a lot."

Tamamo blushed at the fact and was about to say something when sounds of neighing were near. A horse carrying Abe no Yasunari and a carriage arrived. A struggling woman detained by two guards exited the latter. The Onmyouji stepped ahead and greeted Gekkoutane.

"It's my pleasure to meet you in person, Gekkoutane-dono."

"Likewise, Yasunari-dono." Gekkoutane returned the gesture. He eyed the woman. "I presume that's her?"

"My deepest apology, Lady Tamamo. I let her slip out and accused you."

"I-It's fine, Yasunari…"

Gekkoutane approached the woman, who revealed to be a five-tailed kitsune. A quick look at her head and he found out that she was jealous of Tamamo getting more love from the Emperor and not her so she plotted to eliminate Tamomo so she could manipulate the Emperor for her biddings. He relayed this to the others.

"How outrageous!" The samurai captain exclaimed angrily and drew his katana but Yasunari stopped him. The kitsune glared dagger at Tamamo, him and Gekkoutane.

"They are coming for you, O Cursed Wanderer." She said with a sinister grin. "I will wait for you at Yomi."

"No thanks. I like living more." And Gekkoutane swiftly drew his blade and separated her head from body. Abe no Yasunari then proceeded to initiate the exorcism, purifying and banishing the kitsune's soul into the depth of Jigoku. After that, the Onmyoji asked Tamamo to return to the Emperor as she was cleansed of her false accusation but she declined and opted to follow Gekkoutane who had left after the ritual was done. After a week, she finally caught up with him.

"Lady Tamamo, why are you here?"

"I…I want to go with you, Gekkoutane-dono. I want to repay my debt to you."

Gekkoutane frowned as even without his Eyes, he could tell that Tamamo was in love with him. He wanted to refuse her outright like he did to many women before but something about her made him hesitant.

"I…I afraid I cannot take you with me. I'm a Hunter, my job is to kill Yokais, your kind."

She protested, saying that she wouldn't even care about that. With no option left, he told her that when his journey completed, Gekkoutane would visit her. She believed him and promised that when he saw her again, she would become someone more than Tamamo, who was tainted by lies and deception. Tamamo gave him a large bag of money as a small gift to help him on his way. He gladly accepted and before he could say goodbye, she went for a deep, passionate kiss. They stayed like that for a minute when both needed a breath.

"Well then, I wish you good luck, Gekkou."

"…Likewise, Lady Tamamo."

He didn't know that in their next encounter after a long time, she would become the envoy of Amaterasu under a new name: Yasaka.

In a beautiful night, Gekkoutane stayed in a small inn at the city of Nara, enjoying the summer festival. He had recently finished a contract with Taika no Yoritsugi, an equally famous Onmyoji, in exorcising the vengeful spirit of Sugiwara no Michizane. The Onryou, when exorcised, regained a small moment of sanity and thanked the duo for helping him. The deceased scholar told them the story of his life, a series of betrayals, exile and death. Michizane almost snapped when learning that Gekkoutane was a Fujiwara but upon inspecting his memories, the ghost was relieved that he was far more different than the likes of Fujiwara. The scholar granted him an apparition of a worn book and with Yoritsugi, the book was whole. It was a journal Sugiwara no Michizane had obtained from a retired healer containing various medicines, herbs and antidotes. He believed that Gekkoutane would make use of this in his journey to become the most famous Yokai Hunter, or Slayer as Yoritsugi always joked him about.

The owner of the inn suddenly got paled and urged Gekkoutane to head inside. He was about to ask the reason when he saw a very old man with an elongated gourd-shape head. He looked benign but his Eyes, combined with the owner's fear, said otherwise. This old man was Nurarihyon, leader of the Hyakki Yagyou and the Supreme Commander of all monsters. Gekkoutane cursed; he left his sword and the set of talismans in his room.

"Nyohoho, don't be so alarmed, young Gekkou." The yokai said in a jovial tone. This wouldn't fool Gekkoutane as who would let their guard down in front of one of the most powerful Yokais ever existed. Nurarihyon patted his arm and proceeded to make his way inside. The overwhelming aura forced everyone but Gekkoutane to be respectful to him.

"What's the matter? Come in, young Gekkou! The kind owner is going to serve sake!"

He was dumbfounded at how over-familiar Nurarihyon was to him but he still complied. Reluctantly taking a seat opposite of the yokai, Gekkoutane sat down and lowered his head at him to greet him. The yokai laughed heartily at his gesture and allowed the inn keeper to serve sake. After the first drink, Nura looked at him in the eyes.

"So those are the Judge Eyes. To think I would ever see one again, what an opportunity."

"I don't understand…sir…"

"Aw don't be so formal, just call me Old Man! Nura is fine too."

Nura began to tell the story of a man existing before Emperor Jimmu's unification, his name had been lost in time. The land of Rising Sun was still being overrun by yokais and the man took the mantle to cleanse the land of them but soon got disgusted by human's nature so he switched side and became what would be known as the 'King of Fantasy'. What mattered to Gekkoutane was that, the King possessed the Judge Eyes as well.

"So…What you are trying to say, is that I am this King of Fantasy? Impossible."

"Now now, young Gekkou, I'm not implying that you are the King." Nura used the chopsticks to grab a piece of meat. "You have the potential but you are limiting yourself to the lowly humans. Admit it, you find them evil and corrupted but you hate us Yokais more because of your mother's death. I will not deny that I have a hand in that."

Gekkoutane's eyes widened in surprise and rage but Nura raise a hand.

"To be clear, me and my Hyakki Yagyou were just passing by your village during that year's stroll. But then they stepped in and agitated them to set them on rampage. I tried to control the situation but it was too late, the Onmyojis arrived just in time and started killing us all. I believe they set this up." Nura said with a scowl. In a snap, he transformed from an old man into a young, handsome man with long and protruded hair. "They drained my power and reduced me to a weak state as you saw earlier. They have been scattering across the island to find people with special powers like you to, in their words, 'put them into good use'."

"…Who are they?" Gekkoutane asked, giving the yokai the benefit of doubt.

"They call themselves…Satans."

The next chapter will detail how Gekkoutane loses his first fight against the Satans and his return as Yokai/Human hybrid. Stay tuned!