This fic uses they/them pronouns for Naoto and interprets them as nonbinary, as this is how I feel most comfortable writing them. If this is likely to bother you, don't read! Sorry I'm super bad at writing smut.
Monday he treated Naoto to ice cream. Tuesday, presented them with a freshly-crafted tiny bunny to tuck in their coat pocket when on the job. Wednesday it was a strawberry-patterned gun cozy, and by the time they were presented with a hand-cooked tray of pastel-coloured mochi on Thursday ("Since I know you don't like chocolate"), as well as feeling like a woefully inadequate datefriend, Naoto had to speculate that something was on Kanji's mind.
"Mochi instead of chocolate," they pondered, nibbling at the treats while Kanji chowed down on a grilled steak platter at the food court. "Did I forget Valentine's Day? I'm sorry."
"It ain't Valentine's Day yet, dumbass, it's January."
"Then what's the occasion? I thought we agreed that monthly anniversaries were a trifle frivolous for making any celebration over." Though they knew that Kanji would, given half the chance, shower them with anniversary gifts on a bi-weekly basis, the two of them had made a pact not to pay attention to the dates. It was a rule Kanji had tactfully agreed to, born more out of Naoto's complete inability to think of good gift ideas.
"It ain't our anniversary either." Kanji's voice always became gruff when he was trying not to show feelings of affection, Naoto had noted. Their detective's intuition granted them some boons in the art of dating a punk with a heart of gold, but the current situation had Naoto at a loss.
"Then to what do I owe-"
"Hey, if it isn't little and large!" an obnoxious voice interrupted. Naoto grimaced and doffed their cap at Yosuke who was standing over their table, grinning.
"On the job, Yosuke-senpai?" Kanji asked.
"Nah, I'm on break. Me and Teddie have full shifts today. But between you and the other lovebirds, I don't have anyone to talk to." Following Yosuke's gaze, Naoto noticed Chie and Yukiko under the shade of an umbrella at a corner table of the food court, staring dopily into each other's eyes while sharing a milkshake. They thought they heard Chie dreamily saying "You have the most beautiful mole on your cheek," and decided that was enough eavesdropping.
Yosuke was looking at them with a hopeful puppydog gaze which Naoto was sure Kanji would be unable to resist, and so was taken aback when Kanji firmly said "Sorry, we're kinda having a private date, senpai. Next time."
"Gee, OK, don't wanna interrupt the private date, I'll make myself scarce before you start slurping on each other's faces," Yosuke muttered, dusting off his apron as he walked away.
Naoto cocked an eyebrow at Kanji. "Now you have to tell me what this is about. I don't like being kept in the dark."
"I know you don't," their boyfriend muttered, "I just... I'unno. Kinda hard to say what I mean."
"I'd rather you just did. I mean - all these gifts, I can't think what it's in aid of. I'm aware of your spontaneity with measures of affection, but normally it doesn't extend for this long a period." Naoto was aware they were sounding quite stern for someone who was being treated like a monarch by their significant other, but interpersonal communication wasn't their strongest suit, and Kanji knew that.
"Alright, alright, alright." Kanji ground thumbs into his temple. "Just - can you promise you won't, you know, get creeped out, or hate me forever? I really don't wanna come on too strong, or-"
"I can't make any promises until I know what you intend to say!"
"I want us to have sex!" Kanji blurted.
Naoto could feel their face turning the hue of a tomato as Kanji hastily corrected himself. "I mean - man, that sounded - no, I mean, I would very much like, to have sex, with you, if you are up for that, and if you think we're at that point, and however you wanna do it, or if you don't wanna do it, that's fine, that's really fine, I really don't wanna be pressurin' you here, Naoto-"
"Stop saying 'sex' in public!" Naoto hissed, pulling their cap down over their eyes. "People are looking."
"Sorry! Sorry, I'm really sorry, shit! I'm so bad at this. God. Just - forget I said anything, I'm sorry, I made stuff weird-"
"Kanji, I am amenable to taking this discussion further," Naoto clarified in a low countertenor, "But perhaps somewhere more private."
"Oh." Kanji's eyes went wide. "Oh. Um. Okay."
The interior of Tatsumi Textiles always smelt of vanilla and fresh linen, with golden light filtering through the shoji, and although it wasn't quite home in the same way that the Shirogane manor was, being inside the shop still filled Naoto with calm.
Kanji stood around awkwardly with his hands behind his head. "So... Ma shouldn't be back 'til late. And all our regulars know we're closed up today 'cause she's at the craft store in Okina. So... uh... Yeah. Want a snack? I think there's blueberry muffins left."
"No thank you." Naoto sat down on the sofa and fixed Kanji with a look that meant business. "Further to the subject of intercourse. I've given it some thought as well, as I had suspected from our, ah, previous sessions of 'heavy petting'-" - at this Kanji made a noise like a strangled cat - "-that you probably wanted to take the relationship in that direction."
To be honest, they were describing it in a far more elegant way than what had actually happened - in one of a few stolen sessions of necking on Kanji's bed and fumbling vaguely at each other's chests, Naoto had bucked their hips upwards and encountered what was obviously a fairly impressive clothed erection. Kanji had apologised lots while Naoto assured him in a quasi-paternal manner that it was quite natural, and then Teddie had knocked on the door wanting to play video games, and they hadn't spoken about the matter since.
"Well, yeah, I mean - a man's got certain urges-" Kanji cut himself off guiltily, having tried to reduce his number of statements about what a 'real man' did or didn't do. "-But what matters is if you wanna, Naoto." Naoto loved how their name came out of his mouth, fond and tender, but not compromising the name's masculinity as Teddie did with his 'Nao-chan's.
They looked up at him with a firm expression. "Would I like to have sex with you, Kanji? The long and short of it - yes. The predicament is how."
It was Kanji's turn to turn bright red and flop down next to them on the sofa. "How? I - I mean - you do know how, how it works, right? 'Cause-"
"I'm aware of the standard procedure," Naoto sighed, "amongst heterosexual couples. Unfortunately, when you factor in myself, there are a few... complications."
"Like how?"
They pulled their cap down. "I don't want to be on the receiving end."
"...Is there, uh, is there any other... way?"
"Kanji, please. I've been to the bathhouse for training, though I didn't have the no doubt dubious pleasure of meeting your shadow for myself. Iknow you know there's more to intercourse than penis-in-vagina procreation." Kanji was faintly mouthing "oh my god" as Naoto clinically spoke the anatomical terms, and they wondered how this boy ever got past pubescence.
"...But Naoto, you don't got a ...package." Kanji finally managed.
They gave him a wry and uncharacteristically suggestive smile. "As it happens, my package arrived last Thursday by discreet air mail. It's something I had... wanted to order for a while."
"Wait, what?"
"...Does the term 'strap-on' hold any meaning to you?"
"I don't see why we had to go all the way to your place and then back to mine again," Kanji said for the second time, eyes darting down to the box in Naoto's arms every few seconds as if afraid it would burst open at once for all the shopping district to see. "Couldn't we have stayed at yours? I mean, uh... your bedroom's bigger. Your bed's. Bigger."
"Logistically impossible," Naoto huffed. "Yakushiji-san has the ears of a fox. One strange noise from my room and he would burst in, quite sure that you were, ah, having your wicked way with me."
"Fox ears? That sounds... kinda adorable, even on an old dude."
"It was a metaphor."
"But he wouldn't be too wrong, would he?" Kanji smiled, a slow blush spreading through his cheeks. Kanji's blushes were contagious, and Naoto lowered their head as the two of them hastily stepped inside Tatsumi Textiles and slammed the shoji shut.
"That's disputable. I think you could argue I'll be having my way with you..." Naoto said in a low voice. "And you're sure your mother isn't home until later, correct?"
"Positive. Let's... let's go."
As they mounted the stairs in silence, Kanji automatically averted his eyes from the view of Naoto walking up, and then came to realise this was ridiculous seeing as they were literally about to fuck. "Is it blue?"
"Wh-what?"
"Your. Your thing. Your, uh, dick, or whatever. Did you get a blue one?"
"Why must you assume I need to have everything colour-coordinated? I'm not a child; such things don't matter."
"...But it's blue, isn't it?"
"Shut up."
It was blue, Kanji saw, and not quite the monstrous size that he had envisioned, which came as a relief. Sculpted anatomically correctly, the detached thing lying in the cardboard box looked rather surreal, but it would probably be a very different scenario when it was... On.
"Not too big, eh?" He scratched his head. They were both sat on his bedroom floor leaning over the box like children peering at a trapped frog.
"I didn't want one of unreasonable size." Naoto explained. "Something that might look vaguely correct for a person of my stature. And... I don't want it to hurt you too much."
"Did you, like, have me in mind when you ordered this thing?"
"I - um - well - As we're in a relationship, I can be frank with you. Partly, it's... something I wanted for myself. Just to... to put on, sometimes; it feels right. It combats this feeling that there's something missing between my legs." Kanji was silent at that, and Naoto feared they'd overshared. "I... Kanji, you are still OK with this, aren't you?"
"Yeah, 'course I am. So... I guess I should strip off, or something?"
Naoto gave a small smile. "I wouldn't object."
They idly knelt on the floor while Kanji stood up, rangy and tall and strong, with an uncertain gaze at nothing in particular, and unbuttoned his school shirt. It was not the first time Naoto had seen a bare male chest - when they'd been working at the station before they were kidnapped and certain facts came to light, the male police officers would change shirts in front of them all the time and Naoto would have to not flinch. Kanji was more toned than most of them, though, a little tanned and with a tight six-pack. As he began to work on his belt, Naoto ventured, "Let me."
Standing up and placing a trembling hand on Kanji's golden belt buckle, Naoto raised their gaze to meet his. "Don't blush," they reprimanded, hypocritically.
"Can I kiss you?"
"Please."
Kanji was always achingly gentle in his kisses, hardly daring to part Naoto's lips with his own. Naoto reached their left hand up, placing it first around Kanji's suntanned neck, then dragging it lower down to touch his chest. With their right hand they fiddled away at Kanji's belt, loosing his trousers.
"Naoto," Kanji whispered, moving his mouth from Naoto's rosy lips to their cheek and neck. "Naoto." He ran strong fingers through their fine, chopped hair.
"Can I touch you?" Naoto muttered against his neck.
"Yeah. Yeah, please."
Putting a hand down Kanji's trousers was strange and almost frightening. Naoto was used to slipping down between their own legs and finding nothing external, just a heat to press their fingers to, but now feeling their fingers around Kanji's clothed penis was startlingly real. Kanji inhaled sharply as Naoto curled their fingers around the length and trailed up to the tip, where stickiness was beginning to leak through Kanji's pants. Lowering their head, Naoto kissed a trail down Kanji's chest and loved the way he wriggled underneath their touch, but when they came to be sitting on the ground eye-to-eye with Kanji's crotch, Naoto hesitated.
"Do you mind if I don't - I - sorry. I was going to - I thought I could, ah. I don't think I can put my mouth on it."
At once Kanji knelt down and put his hands bracingly around their shoulders. "Shit, you don't have to! Oh man, I never - I never expected you would. It's fine, Naoto, it's fine. Whatever you're OK with."
"Then I might try getting into this contraption." Naoto fumbled behind them for the strap-on, which was attached via a number of strange-looking little buckles. Pulling down their trousers - fast, like a plaster - and not daring to look at Kanji, in case he was looking at the way their thighs and hips were pale and curved with a too-fine covering of hair, Naoto was instead startled to hear, "Cute boxers..."
...They were the grey ones with bunnies on. Naoto had quite forgotten. "B-be quiet," they mumbled. "...I suppose I'll keep my socks on."
"Doesn't bother me."
"I'll... keep my boxers on, too, if that's... OK. I don't... I don't like how it looks under there."
"Sure." Kanji smiled. "Want my help to do up those straps?"
"I don't think I know where to begin," Naoto admitted, pulling the device up their legs until it fit snugly around their lower abdomen. The blue end was flopping out at a rather ridiculous angle as Kanji sat behind Naoto and carefully tightened the small buckles around their thighs. Feeling Kanji's light touch around there was nice, Naoto decided, but still gave them a huge amount of nerves. But this was Kanji. He wasn't about to suddenly turn away in disgust. He knew what they were packing.
"Haha... Kinda kills the mood now that we have to pause to sort this shit out," Kanji laughed awkwardly.
"Sorry."
"Nah, nah, it's OK. Oh yeah -" Kanji stood up suddenly and rushed to his bedside table. "I'll get the condoms and stuff!"
"You have condoms?"
"My ma bought them for me when I turned 16. Most embarrassing event of my life. Tried to give me the talk too, but I wasn't havin' it. I looked all that shit up on the school computers one lunchtime."
"But - do we need condoms?" Naoto felt that if they had to stand around doing nothing with an erect blue phallus in between their legs for much longer, they were liable to back out of the whole thing.
"Oh... I guess not, huh." Kanji blushed. "Man, I can't think straight. I better get my pants off, too. Oh, and lube! Shit, I don't got any!"
"Don't worry. Some came with the package." Naoto held up a small sachet. "I believe it's, er, flavoured."
"...Ew, man."
"Ew." Naoto agreed. "Shall we begin?"
"I guess. I... should I get on the bed?"
"Y-yes."
"You want me, like... on all fours, or what?"
"No, um - I want to be able to see you. Lie... lie on your back."
He did. Naoto took a moment to take in the sight of Kanji Tatsumi, half-nude, lounging back on his bedspread with a virginal blush. They then steadied themselves, and got on too, awkwardly crawling on all fours to straddle him lightly from above.
"Yours is pushing into mine," Kanji coughed.
"Oh! I can... Oh, I can sort of feel it." Self-consciously, Naoto unbuttoned their smart shirt and threw it aside, leaving only the tight vest binder. Kanji put a hand up. "Is it alright if I... touch? I won't undo it."
"Yeah." Naoto gazed down at Kanji, feeling a strange, but nice, shiver down their spine as Kanji softly ran his hands over their torso. "Nice pecs," Kanji smiled. "Hard."
"Don't make fun of me."
"I ain't. Think you can help me get my pants down?"
"Sure..." Naoto pulled Kanji's trousers and underpants down his legs, not bothering to get them all the way off. There were his pale, hard legs, and most pressingly, huge cock, staring Naoto in the face. Huger than the one they had on.
Naoto's face must have betrayed some show of their shock, because Kanji laughed awkwardly. "Sorry. It's got a little excited."
"No matter at all." Naoto put a hand between Kanji's thighs, running it up to skim over his balls and backwards to the tight pucker behind.
"Geez," Kanji went pale.
"Is this still all right? If it's not, it's fine, we can sort out something else."
"Yeah, no, I - I really wanna." Kanji's face was red. "Nobody else's ever touched there before."
"So you have?"
"Well, yeah, I mean... when I was all confused about stuff, ya know, I figured, let's just see if I like it in the butt."
"And what conclusion did you come to?" Kanji didn't know how a smirk that foxy could suddenly come onto the face of a normally stoic and awkward detective, but he was sure it involved illegal magic.
"I am, uh, indeed a fan. Of butt stuff."
"And... what about here?" Naoto ran a few fingers over the shaft of Kanji's penis, causing him to roll sideways and breathe heavily into the pillow. "Am I the first?"
"Well, Teddie's face got pretty close once..."
"What?"
"At the beach, it's a long story! Anyway, it don't matter. Can you... get going?"
"Oh. Of course." Naoto reached for the lube packet and tore it open, some falling out and landing on Kanji's thighs.
"Cold!"
"Sorry. It's quite full, I didn't realise."
"Probably a good thing."
Naoto delicately ran an index finger along Kanji's leg, scooping up the spilt lube. "I'll just... dive in, then."
Putting your fingers up somebody else's butt, Naoto decided, was probably not the sexiest of activities. Maybe it was better on the receiving end, because Kanji was squirming under their touch, but Naoto felt somewhat ridiculous, straddling Kanji and slowly inserting digits into him, Kanji's body pulling tight beneath their touch, like trying to stopper up a balloon.
"Is that... good?" they asked.
"Yeah. Shit, Naoto." Kanji moaned. "It's so good. C'mon, put it in me, please."
"Maybe I'll make you wait."
"Nooo, I..." Kanji was a mess, red-faced and pleading, his every muscle taut with want. "I want you in me, Naoto, c'mooon..."
"I just need to put some lubricant on my end." Now, at the thought of actually putting their substitute cock inside Kanji, Naoto was feeling less awkward and more aroused, getting hot and slick and tense under the strap-on's base. Rubbing up the shaft with ample amounts of lube, Naoto wrapped their legs around Kanji's own, enjoying the heat coming off him. "I'll go in slow."
Positioning themself carefully, Naoto pushed their hips forward and the tip of the strap-on slid inside Kanji's hole. "Is that OK?" Naoto checked anxiously. "It's a lot bigger than my fingers."
"Yeah... Keep going." Kanji's eyes were squeezed shut and as Naoto earnestly pushed in further, he threw an arm over his face and whimpered an incoherent "ffffuck."
"It hurts?"
"L... little bit. Don't worry. Keep going. Put it all in, Naoto. You're nearly there."
"I feel bad that you're the one encouraging me through this," Naoto muttered, slowly pushing their hips forward once more. "That's nearly the whole thing."
Kanji's cock, they couldn't help but notice, had sprung further upright and was now strained red and leaking. Naoto put a hand around it and rubbed up and down gently. "Does this mean you like what I'm doing?"
"Fuuuuck, Naoto, yes..."
They pulled their hips backwards as nearly the whole thing came out of Kanji with a squelching noise. Continuing to softly rub Kanji's cock from top to bottom, Naoto pushed into him again, faster this time, and harder too, feeling a rush in their own loins at the motion.
"That's it - Nao-" Kanji was actually in tears, although they seemed to be good ones, as his whole body jerked upwards, thrusting into Naoto's fist. "That's it, that's the spot... Do it again, do it again."
Naoto obliged, the heady smell and their own building arousal combining into more eager, relentless thrusts in and out of Kanji, hitting his prostate over and over again, Kanji howling and mewling before he finally came into their hand, then lying still and breathing heavily.
Naoto pulled out. "Is that enough?"
"Is it enough for you?"
"I'll just..." Wiping off their hand on Kanji's already sticky thigh, Naoto shoved it underneath the base of the strap-on, palming at their crotch and quickly bringing themself to a small, earthshattering orgasm.
Naoto looked down at Kanji, who smiled weakly, spent. "Can I kiss you?"
"You can definitely kiss me."
They fell into each other, Naoto sweet and warm and right in Kanji's embrace, and then there was a light cough.
"M-ma!" Kanji yelped, scrambling up and pulling the duvet over them.
"... Naoto-kun will be staying for dinner, I assume?"