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That Would Only Be The Beginning Of Eternity

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It was inevitable that Giyuu wouldn’t remain alone for the rest of his immortal life. 

Just shy of three thousand years of age, he was considered young among the tengus. He protected his mountain and took care of the animals living in it. He guided lost humans out of his mountain and killed other creatures who dared to venture further into his territory until-

“What’s a little kitsune doing here?”

Giyuu had felt the presence of a creature stepping on his mountain. He had let it be, thinking it might be just passing by. But as the sun kept rising higher into the sky, and eventually fell as dusk crept in, the creature was still around and it had travelled further into his mountain.

Giyuu stretched his midnight wings into their full size and summoned his sword. He flew to where he felt the presence and positioned himself to fight. But what he saw was an injured kitsune with a swollen ankle. It shapeshifted in its human form but its tails - all nine of them - bristled the moment the creature’s gaze fell upon him. It wasn’t just a common kitsune. It was a kyuubi-no-kitsune.

He didn’t know what had caused him to lose his fighting stance and landed on the ground. His wings curled behind his back. Perhaps its eyes reminded him the colour of sunrise. Perhaps the creature wasn’t in a state to fight except defend itself.

It stopped growling the moment he asked the creature a question. Its expression turned curious and surprised, maybe it’s the first time for the kitsune to see a tengu who didn’t attack with their blades first and talk later. The kitsune’s nose twitched as if trying to scent him of his intention.

It spoke. “I seek refuge in your mountain for a few days and then I’ll leave.” 

Giyuu couldn’t help it but get slightly distracted with the fluffy nine tails flicking left and right. He had fought and killed a few kitsune but never in his thousand years of living had he seen an actual kyuubi-no-kitsune real up close. His jaw looked soft, his cheeks round and pink, and there was something sweet like the dawn stars in those big doe eyes.

“I promise I won’t bother you,” the kitsune added faintly.

Giyuu could sense the creature was being genuine. He had no doubt the kitsune could be a formidable foe, proven from the nine tails which were now fidgeting nervously, but he sounded kind. 

“I’ll take your word for it.” Giyuu flapped his wings, a few feathers drifted around them, and flew back to the top of the mountain.

The next day, the tengu left herbs for its wound. He placed them in front of a den that once belonged to an old wild boar. The kitsune was resting in there for now. He also left a large bowl of clean spring water and a dead rabbit for its sustenance. 

He kept doing it for a few days and one day, when he came back to lay a squirrel meat, he saw shiny coloured rocks inside the bowl that he was supposed to refill with clean water. The kitsune must have searched painstakingly for them in the river. Giyuu couldn’t understand why his chest filled with warmth. He wasn’t expecting anything in return but this felt nice.

A few more days later, he caught sight of the kitsune walking towards the den. He must have just come back from a bath in a nearby lake because the fur of its tails were wet. White snow robe hung loosely on a slender muscular frame. It made the creature in front of him look innocent and pure. Untainted. An unmated kyuubi-no-kitsune. 

The kitsune stopped in its tracks when he noticed Giyuu’s presence, then grabbed the checkered green-and-black outer robe and covered himself. He stood in front of Giyuu and greeted him with a bow of his head. Giyuu nodded back. He scrutinised for any visible scars but there’s none except the one on the left side of its forehead. It must be from an old injury. Its earrings, which Giyuu suspected held some kind of ward against the enemy, swayed gently with the wind. Its ankle was no longer swollen. 

The kitsune broke the tense silence between them. “My name is Kamado Tanjirou.”

When a creature surrenders their name to another creature, it signifies they trust the other with its life. It was odd because the kitsune wasn’t supposed to do that, especially towards a tengu. This strange kitsune might be an idiot.

He could say the same for himself though, since he surrendered his name to the kitsune. “Tomioka Giyuu.”

A name could be a powerful tool to destroy one’s life.

(or to build a life together for eternity)


One cycle of moon had ended and the kitsune was still staying on his mountain as the new moon had already begun. He noticed Tanjirou was grooming himself regularly as if trying to catch someone’s attention. 

Giyuu was suspicious that someone might be the tengu since he’s the only creature staying on this mountain other than the animals. Tanjirou’s shoulder-length scarlet hair was shinier, the fur on all his nine tails were glistening, his shapeshifted skin seemed dewy and silken. Except for his scent. Tanjirou’s scent was thick and cloying that it sickened him but-

But his scent stuck on Giyuu and followed into his dream. 

(and he dreamed about nine tails curling around him as he fucked Tanjirou hard and fast and Tanjirou took his cock so well like a good little mate)


A kitsune should not have such an effect on him but this one did. Strangely, Giyuu started building a nest. What made the entire situation even more bizarre was he had instinctively built a large nest for a different species. A nest that was supposed to perch on a tree had become under a tree - on the forest ground - and meant for a mate that didn’t live in a tree and couldn’t fly.

A mate that couldn’t lay eggs. Besides, Tanjirou is a male kitsune who doesn’t have a womb.

Giyuu’s nose flared in determination. Who cared about that. He could smell the impending rut from the kitsune and all he desired right now was to fuck Tanjirou in the nest that he made for them.

Woven grasses and twigs laid out into a round shape as the base and the side of the nest. One day, as he was bringing mud from the lake and flying back to where he left the nest, he happened to look down and saw Tanjirou in his kitsune form, watching him from the ground. Then the honey russet-furred kitsune followed him.

When the tengu landed on the ground and folded his wings behind him, he watched the kitsune sniffing the nest curiously for a while. He wasn’t bothered when the kitsune stepped into the nest and inspected the inside with its snout. Then, just as the kitsune appeared so suddenly, he left quickly.

Giyuu started reinforcing the twigs and grasses together with the mud and murmuring spells which would strengthen further the nest. Giyuu continued his work on the nest almost obsessively, flying a few times to the lake to get more mud. He kept working and casting his spells until the sun dipped, turning the sky into a colour that reminded him of a certain kitsune’s eyes.

Tanjirou appeared, and this time he had shapeshifted back into his human form, his tails were waving happily. He had a bundle of furs in his arms. As if guided by instinct, the kitsune sat inside and laid one by one of the fur on the base of the nest, placing certain fur on a certain part of the nest.

“Those furs came from the animals I gave as your sustenance,” Giyuu stated softly. His heart soared, touched by the gesture.

“Yes. They are your gifts for me.” Tanjirou blinked suddenly and looked around the nest, as if only realising what he had done. He raised his gaze to Giyuu, his cheeks had a deep flush like apple blossom. His tails were fidgeting restlessly. 

“Uh, I hope I didn’t intrude-”

“This nest is ours,” Giyuu blurted out.


Now it was his turn to blush. He swallowed. A female tengu would have understood when they saw the nest and would proceed with the mating ritual. Even though this was his first time courting, it was ingrained in his instinct to show he was ready to give a home to his potential mate and future broods.

Tanjirou smiled, but there was a gleam of mischief in his eyes.

“Do you desire me, Tengu-san?”  

“I desire to fuck you,” Giyuu replied bluntly.

His mischievousness disappeared and immediately replaced with embarrassment and arousal. Yes. He could smell the other’s arousal very plainly but he knew Tanjirou wasn’t ready yet. Give it a few more days and the kitsune would be begging to be fucked.

So they spent a few days together with Tanjirou sticking to him closely while giving him playful nip here and there, leaving marks on any part of his exposed skin and he wondered if that was some kind of a courtship ritual. When Tanjirou in his kitsune form, he would affectionately butt his head all over Giyuu’s legs and thighs, his tails curled over Giyuu, rubbing his scent all over the tengu. Giyuu wouldn’t hesitate to bury his hands into soft russet fur. He was allowed to hold and caress each of Tanjirou’s tails. They were truly magnificent and he knew that with a single slam from the tail, it could end a creature’s life. Sometimes he would transform into a karasu and perched on the kitsune’s head, watching the sunrise together.

Tanjirou had left his den and started to sleep in the nest. Giyuu too had left his tree on top of the mountain and stayed with Tanjirou. The large nest had not only filled with more furs but had been decorated with the shiny colourful rocks that Tanjirou had started giving to him since their acquaintance. Giyuu continued to cast spells and place wards around the nest, so that no predators or any other creatures would disturb them once the mating season commenced. He noticed Tanjirou preferred to bathe in the river in his human form and he would draw invisible spells on his stomach with the tip of his finger. He wondered what that might be.

Giyuu showed his sword-fighting dance to demonstrate his fitness and skills to his potential mate. A female tengu would have joined in but Tanjirou just sat quietly in his nest, his head resting on his hand with hooded eyes brimming in admiration and lust. All his nine tails wagging excitedly. He knew that he was showing his excitement too as his own wings flapped and fluttered in response.

That night, exactly two moons Tanjirou had been living on Giyuu’s mountain, the kitsune’s heat took over. Giyuu was awakened with kisses peppered all over his face. Then he felt something else that he didn’t expect; wetness all over his front.

Tanjirou was already naked and he was grinding on Giyuu’s slowly hardening cock. There was something wet between Tanjirou’s legs. He immediately sat up and Tanjirou fell on his laps.

Giyuu grabbed both of Tanjirou’s knees and pushed them to either side. Tanjirou’s cock was dripping pre-cum to his laps but what caught his sight was the slit that shouldn’t belong to a male kitsune. He gazed hungrily over the parting fold, so wet with more slick trickling out.

He wondered if all male kitsune had this secret between their legs or only Tanjirou because he was special. Because he managed to capture a tengu’s heart that was made of stone. 

He has a womb. He could carry. Wait. Is it even possible for a tengu’s seeds to bear fruit inside a kitsune’s womb?

“I can smell your delight, Tengu-san,” Tanjirou spoke, his voice rasped with lust.

Giyuu’s heart trembled erratically like summer’s gale. He stared at Tanjirou. He looked absolutely beautiful and utterly sinful with his knees still splayed open, his cock swollen and his cunt displayed like the first spring rose.

“I want to taste you,” he said instead, as he let go one of Tanjirou’s knees.

He reached out and rubbed two fingers between the folds. He sank both digits into silken flesh. “I want to be inside you.”

It was hot, and wet, and soft and he pressed a third finger inside. “I want to breed you.”

Tanjirou started thrusting. “Then do it. Fuck me.” 

He watched his three fingers dipped in and out of the kitsune’s sex. Tanjirou mewled, “I need more. Need- ah- your cock."

He was so aroused and couldn’t wait to bury his cock inside Tanjirou’s cunt. He could always taste Tanjirou’s slick later. So he kissed Tanjirou and spun the kitsune around on his hands and knees, his butt jutting out. His tails were fluffing up and moving everywhere. Giyuu had to physically grab all his nine tails and pressed them against Tanjirou’s side as he held the hip there.

Before he could align his cock into his entrance, he heard Tanjirou whispered nervously, “Be gentle. I’ve never been with anyone before.”

He halted momentarily. So it was true then that Tanjirou was unmated. He didn’t know why hearing that Tanjirou was untouched aroused him even more. He leaned down and kissed Tanjirou’s shoulder, nibbled a patch of skin there to leave a bruise. “Don’t worry. I’ll take care of you.” 

Giyuu whispered in his ear, “Do you trust me?”

He felt the kitsune nodding against him. “With my whole life,” Tanjirou vowed.

He took hold of his swollen cock and guided between Tanjirou’s fold. He pushed in slowly when he felt the kitsune tense under him. His other hand that wasn’t holding the tails, reached underneath and started stroking Tanjirou’s hard length. Once his cock fully sheathed inside the kitsune, he crooned at Tanjirou, waiting patiently for the other to fully relax. It felt like forever but finally, Tanjirou started rutting against him. A gasp escaped between his lips then he pushed his cock in and out of the tight cunt at a steady pace.

Tanjirou was giving Giyuu his purity so the tengu wanted his first time as something to remember even a thousand years later. If possible, he made sure Tanjirou wouldn’t ever seek anyone’s cock but his after this.

A tengu mate for life with one sole partner. But kitsune were polygamous creatures. They have several mates in their lifetime. Giyuu didn’t want that. He was Tanjirou’s first and he wanted to be Tanjirou’s final and only mate too.

Eventually, his thrust became frantic. His wings flared and flapped wildly. Tanjirou was loud as he wailed at every slammed of Giyuu’s cock. He could feel the tails twitching under his bruising grip.

A few more strokes on Tanjirou’s cock and the kitsune suddenly came, but his cunt hasn't reached its peak yet. Giyuu was going to remedy that. He let go of Tanjirou’s softened cock, followed his instinct and rubbed the clitoris roughly with his fingers as he snapped his hips fervently. Tanjirou howled and a moment later, his cunt squirting all over his cock. The wall of the tight passage clenched over his cock and the tengu reached his climax far sooner than he liked. He groaned, stars exploding behind his eyelids as he kept thrusting sloppily, his seeds coating Tanjirou’s cunt. His soul might as well left his vessel for a moment.

They both were breathing harshly. Before he could pull out, Tanjirou whined, “No!” His cunt tightened over his limp cock.

“Wha- why?”

“Knot…” Tanjirou trailed off.

Oh. Right. Kitsune has a knot which would make them stuck together for some time. A tengu didn’t have a knot. So he had to let his length stay inside Tanjirou. He didn’t know how he knew this but he instinctively knew his flaccid cock inside Tanjirou’s cunt wouldn’t be a good replacement as a knot. Then he had an idea. His slick-stained hand slipped easily inside Tanjirou’s sex as he dragged out his softened cock. 

Tanjirou whimpered, realising what he had done but quiet down when Giyuu had replaced his cock with his entire fist and made sure to press hard pressure on the rim of his cervix. It may not be the exact knot Tanjirou wanted but it’s better than no knot at all.

Tanjirou sighed in relief. Then his hand grabbed Giyuu’s head to kiss him. 

“I’ve chosen well. You’re such a good mate to me,” Tanjirou said with a dreamy tone against his mouth.

Mate. Tanjirou had just referred to him as his mate.

The next heat came a few more times, and Giyuu continuously fucked Tanjirou even when dawn appeared and the sun started rising higher and higher into the bright blue sky. He presumed a female tengu would have not lasted this long.

But his mate was a different species. A kitsune, or specifically a kyuubi-no-kitsune that was legendary known to be constantly on a state of arousal for as long as a few moons when they’re in heat or rut. It’s one of the main reasons why they need a few mates to satiate them.

Giyuu was confident he could keep up with his mate. He spent a hundred years fighting a dragon that was as old as the earth without a single rest and conquered the mountain by winning the bloody battle. So he would accept the challenge to fuck Tanjirou for years without stopping if he must.

Perhaps he had been affected by the kitsune’s state of arousal and his instinct was to make sure to breed his mate properly. So he rarely felt the need to rest and only sleep when his mate slept, eat when his mate ate, and a few times he caught himself thrusting into Tanjirou’s cunt as the kitsune was drinking from a nearby stream.

Their mating was mostly frenzied and rough. Only a few words were exchanged between them with Tanjirou constantly screaming and moaning in ecstasy and him grunting and panting in arousal.

Once he had summoned his sword and used the hilt to push inside Tanjirou as a knot replacement. “Is this alright with you?”

Tanjirou merely hummed in pleasure as he laid on the front of his body, his rear being held by Giyuu. He nipped one of Tanjirou’s furry ears. When the kitsune wasn’t able to control most of his transformation during their copulation, a pair of kitsune’s ears would sprout out to replace his human ears. 

“Did you regret that you choose a mate who doesn’t have a knot?” he asked Tanjirou.

His ears twitching occasionally and his tails wrapped comfortably around the tengu. “I don’t need a real knot to satisfy me.” 

He turned his head to smile tenderly at Giyuu. The tengu leaned over the kitsune’s back and crushed his mouth to Tanjirou. 

“You’re all I wanted as a mate,” Tanjirou drawled once he pulled away. The fire in his loins lit up and Giyuu pulled out the hilt and let his sword vanish into thin air. With renewed energy, he spread the swollen labia with his two fingers and pushed his cock inside Tanjirou’s velvet heat.

Tanjirou gasped. “Ngh. You’re so big- ah!”

He grabbed the kitsune’s hips and dragged his cock in and out. Tanjirou’s tails moved languidly with the rhythm of his thrust.

“Will you carry my broods?”

“Ah- yes! I- ah! Carry all our cubs- mmph! As long as you let me!” Tanjirou howled as Giyuu thrust furiously.

(in hindsight, he knew it was impossible but he hoped and prayed and growled that it would happen)


After six moons of intense and wild copulation, Tanjirou’s heat was finally over. When they met, spring had just started and now, winter was already upon them. Tanjirou had been staying on his mountain for almost a year. Giyuu took note of the changes in the kitsune after their long mating period. He looked more relaxed as if a weight had lifted from his shoulders. But the prominent changes were the colour of his inner robe that used to be white had turned to black. Tanjirou told him the robe was known as a kitsune’s intimate robe. It changed colour when the owner of the robe entered a new pack and mated with the head of the pack.

“It means that we’re bonded,” Tanjirou told him.

“So the white robe symbolises purity?”

“Yes. If any kitsune saw me now, they knew by sight that I’ve been marked by my mate’s essence. But I’ve never seen any mated kitsune with a black robe.”

“What do you mean?”

“Their robes would turn into other colours but never black. It’s the first time I’ve seen this.”

Giyuu frowned. He felt a nervous ripple run through his wings. “Is it a bad omen?”

Tanjirou shook his head. “I don’t feel any negative energy. I think because black is your colour. It’s the colour of your karasu feathers, the colour of the sky when the first time we met-”

“And the first time we mated,” added Giyuu with a slight smirk.

Tanjirou burst into a fit of giggle. “Are you still horny for me?”

“Always. Will you still let me take you?”

“Of course. Just because my heat is over does not mean I wouldn’t let you touch me.”

Tanjirou suddenly turned solemn. He sighed, and then murmured, “I never told you why I ended up on your mountain.”

Giyuu brushed his hair and gave a playful tug on one of his earrings. “You don’t have to tell me if you’re not ready.”

Tanjirou gave him a half-smile. He started telling Giyuu about his past. “All my siblings, including myself, were promised to other kitsune packs. At least Nezuko, my sister, mated to a kitsune that she favoured.” 

His eyes had a distant faraway look. “I was supposed to be given away to a very powerful pack. The head of the pack has exactly twelve mates. I’ve met him a few times when I was young and I always sensed something malicious inside him.” 

Tanjirou’s voice started to waver. “I found out that he ended his mates’ lives whenever they are no longer useful to him. He murdered some of his cubs if they went against him. After I endured my trials and received my ninth tail, my pack chose me to be his mate after one of them died recently. So I fought and ran away.”

He moved to sit in Giyuu’s laps and snuggled into the tengu’s chest, seeking comfort. “The reason I’m telling you this because he might track me down.”

Giyuu tightened his arms around Tanjirou. Rage swept over him like a wildfire. Just the thought of someone taking his mate away made him want to seek this creature now and end his life. He growled, “If he takes one step on this mountain, I’ll kill him.”

Tanjirou leaned back and met his eyes. “No. We’ll kill him together.”

“Together,” Giyuu repeated. His chest throbbed at how fortunate he was to find a strong mate.

Tanjirou kissed him fiercely, all heat and spark, and the world around them faded.

When they finally separated, Giyuu saw the unbridled happiness in tawny eyes, his nine tails were fluffed up and waving excitedly. His wings fluttered as they reacted to his mate’s excitement.

“Giyuu-san,” Tanjirou uttered his name sweetly, his own name sounded like honey to his ears. “I’ve got something to show you.” 

Tanjirou took the tengu’s hand and pressed it on his flat stomach. All of a sudden, the air in his lungs had been stolen from him as realisation dawned on him. “A miracle,” Giyuu uttered breathlessly.

(he would kill a thousand dragons, conquered every mountain, wage war on all creatures, and shed his entire immortal blood for Kamado Tanjirou)