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"Are you ready?"
"I am!"
"Alright," said Giyuu.
They stared at each other in silence for a few minutes, then Tanjirou threw his arms around him and pressed him into the futon on the ground. Their foreheads smacked painfully together, and Giyuu hid his wince.
Tanjirou had grown his hair out over the past year, and the curling ends of it brushed against Giyuu's shoulder when he moved his head. His hand slipped down and untied both their yukata, and the thin fabric pooled on the floor beside them. Skin brushed against skin, and the temperature of the room quietly rose.
When it came to actually embracing someone, Giyuu only had a vague theoretical notion about how to proceed. Most demon slayers had experienced some form of tragedy in the past, and were therefore too preoccupied with the idea of revenge to consider anything unrelated, such as love. Giyuu had always lived with the belief that he would never live to see the end of the long night, considering he hadn't deserved his position as the Water Pillar in the first place. He hadn’t had time to think about love either, until Kamado Tanjirou appeared.
Tanjirou taught him to live for both himself and Sabito's memory, and had been the first ray of light that broke through the darkness and heralded the coming of dawn. He defeated Kibutsuji Muzan, and ended the nightmare of human suffering in their generation.
The next three years after the final battle were dedicated to mourning their lost comrades and planting flowers over the graves of the dead. Everything wasn't over just yet--there were still demons turned by Kibutsuji wreaking havoc throughout the land. Under the guidance of Ubuyashiki Kiriya, the Demon Slaying Corps regrouped and redirected their efforts to seeking out any remaining demons, administering the cure to those who were still redeemable. As for the ones who had long lost their humanity, they put them to rest.
With time, the wounds left by the ones who had passed away finally began to close. Demon sightings were on the rapid decline, and they could now afford to act in large groups and take breaks between missions. The Pillars' meetings were now dedicated to coming up with a sustainable business model for the soon-to-be unemployed masses, since it was projected that most demon slayers would be able to retire within the next five years. Giyuu didn't consider himself ambitious or creative in the slightest, and tended to zone out during these meetings.
For the first time since he picked up the nichirin blade, Giyuu now had extra time to think about what he wanted to do with his life, and who he wanted to do.
Uzui had offered to give him bedroom advice after he caught wind of their courtship, but Giyuu had forcefully declined. But now, as he hovered over Tanjirou with one hand in his lover’s nether regions and a jar of oil in the other, he kind of regretted not researching this more thoroughly.
Tanjirou patted his head with a fond expression. "Giyuu-san, it'll be easier if you coat your fingers with the oil."
"Oh. I see."
(Asking someone from the Butterfly Estate for an oil or a cream to misappropriate was too mortifying to think about, and Tanjirou didn't trust himself to lie about his intentions. Tanjirou also didn't want to associate the smell of the ointment Urokodaki gave him with anything sexual, which meant that there was only one option left: they would have to purchase something on their own.
After smelling the entire aisle of scented oils, Tanjirou had finally settled on the most exotic one he could find.
"This way I won't ever run into this smell in everyday life," he explained cheerfully. "It'll be our special thing."
Giyuu secretly marvelled at how Tanjirou could say these things without feeling embarrassed. They bought a different jar of oil as a decoy before heading home, which was crucial for their plan’s success.
Tanjirou had come up with an elaborate and overly complicated lie over the past few weeks involving a sudden interest in massages and a hands-on application of his learning. To make the experience more authentic, he had even started offering massages to Inosuke and Nezuko over the past few weeks. Tanjirou was essentially gaslighting himself into believing that he hadn't bought the oil for inappropriate purposes. It was probably the only way he could get away with hiding something from his little sister, and thankfully Nezuko seemed convinced.
In the same vein as the oil debacle, Tanjirou and Giyuu spent hours agonizing over when and where they could do the deed and still get away with it. Nezuko was home on most days, and she still had the habit left over from her time as a demon of sleeping in Tanjirou's room occasionally. Meanwhile, Inosuke's behaviour was erratic and couldn't be predicted, which meant that he was equally likely to barge into their room at random hours of the night. Not to mention all the other people who dropped by to visit them and would never let them live it down if they ever found out: Genya, Muichirou, Kanao, Urokodaki... Zenitsu was the only one they didn’t need to worry about. He usually tired himself out with his relentless screaming during the day and always went to bed pretty early.
One month in July, almost two months after they bought the oil, Nezuko declared that she would be sleeping over at the Butterfly Estate with Kanao. It was a girl’s night out and Tanjirou and Zenitsu weren’t invited, which was all for the better. Inosuke was gone on his training trip with Genya, so he was also out of the equation. Muichirou had just visited them a few days ago, and it would be a while before he was back from his mission. The stars had finally aligned, and Tanjirou could barely contain his nervous energy in the days leading up to the date they had finally set. Giyuu was a bit more composed than him, but he also found himself blanking out at random intervals during the day out of apprehension.)
"--yuu-san?"
Had he blanked out just now? Oh no. This was much more difficult than he had imagined. Wasn't the act of procreation supposed to come naturally to everyone?
"You can stop calling it an "act of procreation", you know. We can't exactly procreate."
Did he say that out loud by accident?
"Yes."
"I'm sorry," he replied automatically. "Do you want me to--"
"No, it's fine! If you just--"
“Like this?”
"..."
Tanjirou sucked in a sharp breath as Giyuu pushed himself in.
"Yes, a-ah! "
Arms looped around his neck tightly, and Tanjirou’s thighs shook with the strain. A bead of sweat slid down Giyuu's temple and landed on the smooth stretch of skin on Tanjirou's neck. He leaned down and gently licked it off.
The flame of the candle quivered in the heat of the room, and melted wax slowly slid down the side of its pale length. The room was silent except for the sound of their panting.
Tanjirou's eyes were squeezed shut out of nervousness. "Is it...is it all the way in yet?"
Giyuu's stomach sank. He really didn't want to say it, he wasn't going to say it--
"...I think I'm stuck."
Tanjirou burst out laughing, and Giyuu gave him a slightly betrayed look. He was already getting soft from the sheer awkwardness of the situation, and he wondered if he should just give up for the night. Maybe he would take Uzui up on his offer after all.
Soft lips pressed against his cheek in a feather-light kiss, breaking him out of his reverie. Giyuu looked down, and Tanjirou's bright eyes glimmered up at him with affection.
"It's okay," his lover whispered into his ear. "You can be a little rougher with me, you won't break me."
It was as if someone had dug his heart out of his chest and dropped it into a vat of boiling oil. Giyuu wasn't very good with words, and he didn't know how exactly to express the depth of the emotion he felt in that moment. Instead, he pressed their lips together, and hoped that he understood.
Tanjirou responded eagerly to the kiss, and slipped his tongue into Giyuu's mouth. Was this confirmation? Giyuu had long since given up on trying to guess exactly what he was thinking, because he constantly found himself surprised by Tanjirou's logi--
"Giyuu."
Candlelight flickered over Tanjirou's features as their eyes met. His face had lost its childishness roundness over the years, worn down by the weight of the destiny resting on his back. Yet somehow, he hadn’t changed at all.
"I love you," breathed Tanjirou, pressing his face into Giyuu's shoulder.
He joined their hands together as he began to move, smoothing his thumb over the back of Tanjirou’s hand. There were calluses on both of their palms from years of wielding the blade, and scars littered their bodies.
The mark on Tanjirou's face seemed to burn with a hidden fire when his eyes roamed over it, a silent reminder of the fate they had both been part of. Giyuu’s chest filled with warmth.
"Anything for you," he murmured, watching the way Tanjirou's face went slack with pleasure. "Anything."
They had met in the snowy mountain six years ago, and both had carried a piece of that cold with them wherever they went since then. Kamado Tanjirou had just been another tragedy he was too late to prevent, until the boy became so much more than that.
And now, the snow has finally melted.
The nighttime breeze flowed through the open window, carrying with it the faint scent of summer blossoms. Giyuu set the clean towels aside and laid down on the futon, letting out a contented sigh.
Tanjirou was holding up his haori by the window, waving it back and forth in an unusual motion. Giyuu wondered if this was some kind of Kamado family ritual, or if he was actually sending some kind of secret signal to someone outside.
He studied the movements closely. What was he trying to say? Was it praise, or was it actually a complaint about Giyuu’s performance? ...Was that why Tanjirou couldn’t say it out loud, and had to resort to this sort of charade?
The more he thought about it, the more confused he got. Giyuu sat up abruptly.
"Is there something wrong?"
"Oh, sorry, am I bothering you?" asked Tanjirou, turning to look at him with a bashful smile. "It's just that the smell of is still really strong in here, so I want to air it out a little."
"I don't smell anything," said Giyuu, puzzled.
"Ah, I guess it's just me then." Tanjirou fanned his haori a few more times, then shut the window and laid down next to Giyuu on the futon. "I'm sorry, I know I get bothered by smells far too easily."
"It's a gift you should be proud of," Giyuu told him.
Tanjirou beamed at him and threaded their fingers together under the covers. They blew out the light, and settled in for the night.
Just before he fell asleep, a thought suddenly crossed Giyuu's mind and his eyes snapped open. "Your friend, Zenitsu, didn't you say he had an enhanced sense too?"
"Yeah, his hearing is very good. Why are you asking?" Tanjirou fiddled idly with the tips of Giyuu's hair, wrapping it around his fingers.
"...Do you think he'd be able to hear us from across the courtyard?"
All the blood drained from Tanjirou's face.
"I...what... why would you even ask me something like that?! " he groaned into the pillow, the tips of his ears flushed a bright pink. "There's no way I can sleep now, I'm going to be thinking about it all night."
"If you can't sleep," Giyuu said slowly, "do you want to go again?"
"NO! ...Yes."
There were dark circles under Zenitsu's eyes at breakfast the next morning.