A/n: Some redpants nonsense... what it's not a rule that all redpants stories have to end in porn is it? Loosely based on the old woman's proverb 'You know what they say about black lingerie… those who wear it want it to be seen' Johnlock goggles optional

"Astounding." John said, again without thought, amazed by his partner-in-solving-crime's deductions. Sherlock looked smug at the compliment - he usually did when John voiced his admiration.
"Oh come off it! There is NO way you can tell she was a prostitute from the colour of her knickers!" Sally Donovan exclaimed fervently, looking at her boss for back up. Lestrade just shrugged, he had no reason to doubt Sherlock's version of events, and given he'd just named the murderer, he was highly unlikely to call him up on it.

"I'm with Sa-Donovan on this one sir." Anderson piped up, being the little arse-kisser than he is.
"I didn't deduce that she was a prostitute only from the colour of her knickers, if you'd listened you'd have realized I listed several other key factors that lead me to that conclusion. Though you can tell an awful lot about a person by their choice in underwear." Sherlock said, undeterred. "Adversely you can tell the predominant colour and fit of a person's underwear by certain personality traits."
"Oh now you're just bullshitting me." Donovan snapped. Sherlock grinned, a malicious smirk as he surveyed her with deductive eyes. John groaned, Sally really had asked for this.

"Catholic upbringing, but you never did like your mother's decisions, you rebelled as soon as you were old enough, a string of lovers in your teens, some mocked you for your inexperience. From then on you've always been prepared, anticipating a sexual encounter with Anderson tonight, you chose your underwear carefully. Matching most likely. Black push up bra and black lace…" He looked at her and cocked his head as though making a decision there and then. "French knickers I believe."
"You're a freak, you know that!?" Sally spat, a blush rising on her cheeks, she folded her arms across her chest as though he had x-ray vision, she suddenly felt very exposed. Sherlock however was not finished, he turned to Anderson, who almost visibly recoiled.

"Too easy. Anticipating the same sexual encounter as Officer Donovan you decided to forgo the underwear and go… how do they say it, commando?" He smirked and Anderson glowered.
"Lucky guess." He muttered embarrassedly. Undeterred, Sherlock spun on his heel coming face to face with Lestrade who did not look at all embarrassed or ashamed.
"Go on then, give it your best shot." He said, opening his arms wide as though anticipating a bullet.
"Always the officer, Lestrade." Sherlock said grinning like the cat who had the cream. "The boys in blue so to speak, however you're a tad too old in your own opinion to go gadding around in sky blue underwear, so you've opted for the more sensible navy. Despite the fit of briefs being preferable to your uniform, you wear boxers because your estranged wife prefers them." Lestrade simply nodded.
"Bang on." He said appreciatively.
"And that brings us to John." Sherlock said, barely acknowledging the approving gesture from Lestrade, Sherlock turned to face Donovan, with a superior smile as he proceeded to deduce John. "Good old reliable John. Dependable John. Ordinary, plain, no frills attached John." He sounded so confident, so proud of himself, and it pissed John off more than a little bit.
"Oi." He protested.
"Standard fit, white Y-fronts." Sherlock declared. It was John's turn to smirk, for once Sherlock had gotten something wrong.

"No." He said, and the look on Sherlock's face was priceless. His arrogant demeanour cracked like glass and he span to face John with almost fury.
"What do you mean no?" Sherlock demanded.
"I mean, you're wrong." John said firmly, barely noting the ridiculousness of the scenario. Here they were, four fully grown men and an adult woman, stood in an alleyway over a dead prostitute, discussing the colour of John's underwear.
"I'm not wrong." Sherlock argued.
"I think I bloody well know what colour underwear I'm wearing Sherlock." John said, trying to keep the anger out of his voice, truthfully he was a little hurt at Sherlock's description of him as all-but 'boring'. He wouldn't argue the point that yes, the majority of his underwear was plain white (boring) Y-fronts, but today he wasn't wearing them - and he was eternally grateful for his early morning decision to throw this pair on over his others.
"The freak got one wrong!" Said Sally, unable to keep the glee from her voice.
"John's obviously lying." Sherlock said snottily.
"Turn around." John ordered.
"I said turn around." John said in a much firmer tone. Sherlock reluctantly did as told, and John turned to the other three, he slipped a hand below the belt of his jeans and fished out the waistband of his underwear, showing Lestrade, Anderson and even the very female Sally Donovan the brightly coloured, distinctly not white fabric. Sally's grin nearly split her face in two.

"You're wrong, Sherlock." Lestrade confirmed with a smirk. Sherlock spun round and narrowed his eyes at all of them.
"Then you're all lying. It's a conspiracy." He argued vehemently, and stormed off down the alleyway without another word (though John thought he heard an irate yell of 'TAXI') John couldn't help the snigger that fell from his lips, just as Anderson, Donovan and Lestrade couldn't stop the fit of giggling that ensued. It wasn't right, to laugh at their friend and colleague, it really wasn't, but it did feel good to just once put the smug bastard in his place.
"I'll give you a lift home." Lestrade offered, wiping the tears of laughter from his eyes. John nodded and followed Lestrade into the police car.

The car journey was mostly silent, the occasional chuckle from one of them setting the other one off. When the car slowed to a crawl outside 221b Lestrade unlocked the doors for John to get out but called him back.
"John - I have to ask why red?" John grinned boyishly at the question.
"Why not?" He replied, a spring in his step as he walked back into the house. He climbed the stairs with an unbridled happiness - it really wasn't decent to be laughing at his flatmate's expense, but the git did deserve it, just this once. Stepping into his flat though he realised he was going to pay for it - Sherlock was in a massive sulk. In the few minutes he'd been in the flat before John had arrived he'd managed to change into his pyjama pants and his second best dressing gown (the blue one, not the plaid one he only wore when Mycroft popped round) and had plonked himself on the sofa, in his typical Someone-Has-Insulted-My-Massive-Intellect pose, his face and knees against the back of the sofa, his back to the rest of the room.

John didn't say a word, just stuck the kettle on, wiping the smile from his face. He poured two cups of tea, making sure to put sugar in Sherlock's, he placed it on the coffee table. John sipped his own tea and flipped open his laptop.
"You better not be blogging about this!" Sherlock warned venomously. John blinked, he hadn't even started typing yet, Sherlock quite clearly had eyes in the back of his head.
"No." John said calmly. "I'm not blogging about the colour of my underpants." He sipped at his cup before surveying his moody flatmate. "Are you really going to sulk over this?"
"Yes." Came Sherlock's blunt reply.
"So you got it wrong, it was bound to happen eventually Sherlock. You should be grateful that you made a mistake now, when it doesn't matter. I'd much rather you made a wrong guess about my underwear than whether a murderer was likely to shoot or not." John said in what he hoped was a comforting tone.
"I don't guess." Sherlock grumbled. "I make no assumptions. My conclusions are based on solid fact."
"If it makes you feel any better I do predominantly wear white Y-fronts, just not today."
"What's so special about today? It's Monday…"
"Nothing's special about today, I just put my red pants on this morning instead of white ones." John said simply. At this Sherlock rolled over and stared at John incredulously.

"Red?" He repeated, sounding utterly repulsed and incredibly curious at the same time.
"Red." John repeated with a nod.
"Prove it." Sherlock said. John shrugged, stood up and with little regard to decency unbuttoned his jeans, pulled the left side down slightly, showing the top half of his bright red underpants. Sherlock frowned, this revelation new to him. John made himself decent again, and sat down, a slight blush on his cheeks. "Why red?" Sherlock asked perplexed.
"Comic Relief." Seeing Sherlock's puzzled expression John sighed. "You don't know what Comic Relief is? The charity thing they do every year? Red Nose Day? Honestly Sherlock sometimes I think you've spent your entire life living under a rock." John said exasperatedly.
"So… you wear red pants for charity?" Sherlock mused, cocking an eyebrow.
"No, I bought them for charity a few years ago. I wear them because they're comfortable." Sherlock frowned, and reached for his cup of tea.

"I shall have to re-evaluate my deductions of you from now on John Watson." Sherlock said eventually. John made a non-committal noise in the back of his throat. "And once my pride has recovered from this knock I shall ensure that I do not make such rash judgements again."
"Was that an apology?" John asked curiously.
"As close as you're going to get to one yes." John smiled softly. "I will say this though…" Sherlock said, rising from his position on the sofa and heading towards his bedroom. "I may have had you pegged as a white y-fronts man… but the red ones are much more aesthetically pleasing." John blinked at Sherlock's closed door. An apology and a compliment? Then, realizing just how he'd been complimented, John's face turned a very similar colour to his underpants.

A/n: There you go, silly little nonsensical fluffy piece. Reviews are very much appreciated. (And to all my American readers, Red Nose Day/Comic Relief often sell red things for charity, I happen to own a rather lurid pair of red socks in name of the charity!)