Sherlock found out exactly the way John had feared. There was a case - barely a six on Sherlock's completely arbitrary scale - but the relatively tame smuggling ring had quickly turned into a city-wide manhunt and then a long chase through Regent's Park. John even managed to execute a rather spectacular rugby tackle in the end. The breathtaking macho-ness of the maneuver was somewhat sullied by the long slide down the gravel-studded hillside he and the suspect both performed a moment later, however. The suspect ended up in an ambulance; John ended up subjected to Sherlock's questionable medical care back at Baker Street.

"Hold still," Sherlock grumbled. "No telling what got into the wound - that section of the park is rife with-"

"Don't really want to know," John interrupted before Sherlock could get into a full-blown soil sample lecture. "Just hand me the damn flannel and I'll do it myself."

"Not the right angle for you," Sherlock countered. "And it's on your right side. Does it hurt when I do this?"

John nearly levitated away from Sherlock's questing fingers. "It's bloody road rash, you idiot. Of course it hurts!" He twisted to look, but of course Sherlock was right - it was the wrong angle to actually see his own hip properly, especially with his jumper all bunched up around his armpits to keep it out of the way. "Help me get this damn thing off?" he finally asked. "Can't see."

"You don't have to," Sherlock grumbled, but he helped John get the muddy jumper off over his head. "Trousers and pants too - up now."

"Hell no." Going shirtless was one thing - it's not like Sherlock had never seen his bullet scar before - but stripping completely was something else entirely. "I'm not getting naked for you no matter how much you make that hopeful I-can-make-John-do-what-I-want face. Yes, that one. Work around them. Or give me the damn ointment."

"In a minute." Sherlock daubed one more time with the damp flannel, dislodging a final piece of grit from John's ribcage, then squeezed some antiseptic paste onto his fingertip and smeared it surprisingly gently onto the reddened mess of scrapes running down John's side. He worked it in thoroughly but efficiently, frowning in concentration as he went. John was just starting to relax into the feel of the cool ointment soothing the painful raw feeling when Sherlock got to the bottom of what he could reach - and just kept going, dragging John's waistband down along with his hand.

"Sherlock-"

"Hush," Sherlock snapped. "The scrapes go all the way down your hip, and neither of us are going to be able to do much about it unless you take these ridiculous trousers off."

John considered protesting further - it's not like he couldn't do this part himself, later, in the loo with the door closed - but Sherlock was being spectacularly gentle and the ointment really did feel nice. He finally relented enough to unzip his trousers (which were loose already, a result of him having lost a bit of weight chasing after Sherlock all the damn time, which was probably why gravel had even managed to get down his pants in the first place) and slide them carefully down to mid-thigh. He kept his pants determinedly on. With luck, Sherlock wouldn't notice-

He noticed. Of course he noticed. Sherlock bloody Holmes notices everything. Luckily John wasn't the least bit hard - that would have been embarrassing - but Sherlock's confident touch faltered the moment his head turned a bit and he caught sight of John's cock bulging against the confines of his pants. His unusually large, no-way-Sherlock-won't-comment cock. Sherlock blinked once, twice, then inhaled slowly and opened his mouth to speak-

"I swear," John cut in, "if you say one word about standard deviations from the mean I will punch you, half-dressed or no."

Sherlock closed his mouth.

"Are you done?"

Sherlock hastily smeared the rest of the cream over John's hip and sat back. "John-"

"Don't." John stood and yanked his trousers back up, the fabric abrading on the fresh scrapes and making him clench his jaw against the sudden pain. "Just . . . I don't suppose you can delete that, can you?"

Sherlock looked up at him, lip between his teeth. "I don't know if I . . ."

"Please. I don't need you ridiculing me, or making reference to my statistically deviant prick next time you meet some future girlfriend of mine, or bringing it up in front of the Yard. Just pretend you don't know. I'm going upstairs."

And he went, leaving Sherlock sitting alone in the living room with a half-empty tube of antiseptic ointment and a strange, wary look on his face.

Sherlock stared at him. Often. It wasn't blatant, not eyes-on-John's-crotch 24/7, but it was enough that John started sitting with his Union Jack pillow in his lap when he was writing his blog entries or just watching telly on the sofa. Sherlock wasn't put off one bit by John's obvious disinclination to talk about it. Then again, Sherlock was bollocks at social cues a good portion of the time so that shouldn't have been much of a surprise.

"You know," Sherlock said the next Saturday morning, when John was enjoying a leisurely breakfast and the first real day off he'd had in two weeks, "I couldn't help but notice-"

Knew this was coming. "I told you to delete it," John grumbled.

"And I told you I couldn't. But John. John." Sherlock swung the other chair around and sat on it backwards, slotting his pajama-clad legs through the holes under the armrests with a lithe grace John could never have achieved even before getting shot in Afghanistan. "Penis size is assumed to correlate with an individual's status in the social hierarchy. Hence popular reference to 'dick-measuring contests' and the like. But you don't do that."

"No," John agreed, and took a fortifying gulp of his tea. When Sherlock got locked onto something it was worse than useless to try to dissuade him - embarrassing as this was, it was best to just ride out the conversation and then hopefully Sherlock would get over it. The only saving grace was that Sherlock likely had no bloody idea how rude he was being, so the embarrassment in the room was entirely one-sided. "Hardly a point, is there? And usually the comparisons are metaphorical."

"You had communal quarters in the army," Sherlock pointed out. "More literal there?"

Christ. John stared up at the ceiling. "Got a bit of teasing for it, yeah. But not as bad as it would have been the other way around."

"If your penis were significantly smaller than the mean?"

"Sherlock, pardon my intrusiveness-" - John leaned hard on the word - "-but why the fuck do you care? I have wider-than-average feet too; are you going to ask to measure them next?"

"I've already learned all I can from your shoes," Sherlock declared, waving John's misdirection away. "But I - wait." His eyes widened. "You'd let me measure?"

"I was not offering."

"But you wouldn't entirely rule it out." Sherlock expression shifted into something disturbingly similar to the one he got when he was on a case and was thirty seconds from that lightning bolt of insight that inevitably solved everything. "John. John. If I were to volunteer to . . ." He trailed off, drumming his fingers on the table in a syncopated rhythm. "What is it you want?"

"I'm not the one begging to put a ruler to my flatmate's dick," John said dryly.

"Ruler would be imprecise," Sherlock said absently. "Much better to - oh! What if I were to promise to clean out the refrigerator?"

"You're about twelve hours too late," John said, and returned to his tea. "I binned those intestines last night. And the frozen mice."

Any further remnants of conversation were lost by Sherlock dashing to the refrigerator, yanking it open, and staring in horror at the pristine shelves. He then locked himself in his room and wouldn't come out for the rest of the day.

"I'll come to the Yard Christmas party."

"You'll do that anyway."

Sherlock scowled. "Only under sufferance - I'll go and pretend I'm having fun."

"Oh, right." John rolled his eyes. "You're discounting the fact that the rest of us enjoy ourselves a lot more when you're not, as you put it, 'having fun.' You're hilarious when you're all brooding and grumpy and Anderson is too drunk to understand your insults."

Sherlock glared, but didn't deny it.

"I'll proofread your next ten blog posts?"

"Ta, but no. I get enough of you telling me I'm an idiot already."

"I'll refuse to comment on your next ten blog posts. Even if they're utterly ridiculous."

"Sherlock. No."

"I'm out of ideas," Sherlock confessed several days (and attempts) later. "What if I promise not to involve a numeric scale at all?"

John cracked one eyelid from where he'd been reading (okay, dozing and pretending to read) in his armchair. "Are we still on about the size of my cock? What could you possibly need from me that you couldn't get in some dry academic textbook?"

Sherlock mumbled something.

John blinked, sure he hadn't heard that right. "Come again?"

"I said I want to taste it," Sherlock repeated. "I was going to work up to requesting that, eventually, but I thought you'd be more amenable to something that sounded strictly scientific first. But what if I promise to suck you off - properly - would you be amenable to it then?"

John opened his mouth, but no sound came out. There really wasn't a lot that came to mind, actually. He'd always assumed Sherlock was gay if he was anything - the man used an indecent number of products in his hair - but since he'd never been weird about it and it's not like he was bringing men home, John had always just figured it was best to ignore the whole sexuality aspect of his flatmate's life entirely.

That offer, though. John took a deep breath. He'd always considered himself straight - it wasn't until he moved in with Sherlock that he'd ever so much as thought about it. And really, it's not like he thought about it much. It's just that every once in a while, the light would catch Sherlock just so and John would be struck by how utterly beautiful the man was. It wasn't even Sherlock as a whole - just the angle of a shoulder here, the twist of a lip there. Little snippets that caught John's attention and made him realize that actually, Sherlock was bloody gorgeous, and he'd have to be blind not to notice. Usually then Sherlock would say something rude and the interlude would be over, but still.

"I'm not gay," John blurted out. It was a stupid thing to say, as evidenced by Sherlock's eye roll, but it was the only thing that made it past the tangle of thoughts in John's brain.

"You do have a healthy sexual appetite, though," Sherlock countered. "And I've seen you staring at my mouth."

Oh God, he's noticed. John slumped a little lower in his chair.

"You wouldn't be the first straight man to ignore his partner's gender while in the pursuit of orgasm."

"I - right, fair point, but why would you even want to?" John asked. "This is a bit beyond even your usual complete disregard for social norms."

Sherlock snorted. "Please. Let's not pretend we don't know what's going on here."

Berk. "Maybe use small words," John said dryly. "For those of us with tiny little brains."

"Fine." Sherlock strode across the room to him and dropped to his knees at John's feet, startlingly close and eerily intense. "I. Want. To. Suck. You. Off. I want you to shove your giant cock so far down my throat I choke on it. I want to have to practically unhinge my jaw to swallow you down. Call it a size fetish if you will, but I haven't been able to masturbate without thinking about it since before you took that tumble in the park. I don't want some measurement for science; I want it for me. I've never had a partner as big as you are and I'd very much like to rectify that."

Oh God. "Sherlock-"

"And from your side," Sherlock continued, ignoring John's interruption, "I'm perfectly confident that you've never had someone give you head as well as I do. You've almost certainly had trouble in the past - lovers who couldn't or wouldn't accommodate your larger-than-usual genitalia, who complained that you didn't fit inside them. I'm willing to bet that even the ones who were willing to attempt fellatio universally gave it up as a bad job and just expected you to do without. Tell me I'm wrong."

"You're not," John muttered.

"I'm here, John," Sherlock continued. "I'm here and I'm offering and I'll make it so, so good for you." He bit his lip and looked up at John with limpid eyes, beseeching and seductive both, and John could feel his cock twitching in his pants. Just because of that look and that low, velvety baritone promising a taste of heaven. And suddenly John realized he had no idea why he wasn't already taking advantage of Sherlock's extraordinary mouth.

"Fuck," John groaned, but he reached down and unzipped his trousers anyway.