John slid into the cab after a case on the way back to Baker Street. Basking in the glow of another job well done, John didn't feel his usual sense of ease settling over him. Instead he asked, "Sherlock, what's that...?" He'd been subconsciously trying to sit closer to Sherlock the second he got in the cab. Even now he wanted to sit closer to the detective and breathe in deep. He couldn't resist; he put his face right up next to Sherlock's neck and inhaled. "It's….

"John," Sherlock said wrapping a large hand around John's shoulder in an effort to push him back a bit. "What are you on about?" he replied trying to keep the excitement out of his voice.

"You just smell different, good," John said and pressed a bit closer. He pushed against Sherlock's hand and felt it give a bit as the detective allowed him to press his face closer to his collar.

They'd been together all day working a case and John had noticed an enticing, yet subtle aroma coming from Sherlock whenever he passed close by. He kept getting teasing little whiffs of something he couldn't describe but only wanted to keep breathing in. Sherlock smelled like a fragrant wind over the sand dunes in Afghanistan or like an exotic spice that both enticed and excited the senses. It reminded him of the chase, the thrill of catching criminals and the bringing of them to justice only intensified and rolled into one. How could a scent do all that?

After they'd solved the case, Sherlock suggested dinner. John wanted pizza and Sherlock had nodded in agreement. Between them they devoured an entire large, veggie delight with extra mushrooms. John laughed at Sherlock's retelling of some of the bits he wasn't present for, and all John wanted to do was lean in and smell. He kept thinking of ways to get Sherlock closer to him as nonchalantly as possible. "Hand me a napkin, would you Sherlock? Pass the peppers, please…" Sherlock smiled each time and handed over the requested item letting his arm linger a little longer each time.

John even moved close to Sherlock to wipe off a smidge of sauce from his lips and Sherlock just grinned sheepishly and allowed it. However, John felt forlorn each time Sherlock moved back over to his side of the booth. "Pass the cheese, please?" John said trying get Sherlock back over to his side and so it continued all through lunch. Sherlock didn't seem to mind in the least which should have raised alarm bells for John; but, for some reason, he didn't care at all as long as he kept getting those delicious whiffs of Sherlock.

The scent wafted by at the oddest times. He noticed it when they were in the same room together and especially when they'd ridden the elevator up twenty floors. That particular journey caused him to feel a tingle as the blood rushed south and his jeans tightened up in the crotch. No, no. Sherlock's scent was NOT turning him on! He forced himself to think about bedpans and IV drips while he tried to will away his growing erection. It finally worked and he felt almost back to normal when they got outside and John got a breath of fresh air. He'd managed to forget about the whole incident until they entered the cab together.

"It's incredible," John nearly moaned in his desire to get another smell. Then, he remembered himself. This was his platonic flat mate, his asexual "married to his work" flat mate and here he was practically throwing himself physically at the man in an effort to catch an elusive scent that seemed to sending his libido into overdrive. He stopped himself short of pressing his entire body into Sherlock's and suddenly pulled back. He rolled down the taxi's window to get a breath of fresh air and a sharp autumn wind hit him with enough force to clear his addled brain a bit.

"You noticed?" Sherlock asked looking sideways at him. "I wondered if it would affect you."

"Noticed? It's been driving me crazy all day. What is it? It's incredibly strong right now and I…." John felt pulled like a magnet to move back over to Sherlock's side of the seat and continue pressing his face right into Sherlock's neck.

"It has a cumulative effect, John. It builds up slowly in your system. "It's a cologne I'm developing whose chemical compound is top secret. I thought I'd run an experiment and…"

"Sherlock," John growled. "We've discussed you experimenting on me. You promised me no more drugging after Baskerville."

"I'm not drugging anybody. I'm simply wearing a new cologne that may have an interesting pheromonal effect on some people," Sherlock replied cryptically.

John simply couldn't help himself and slid the rest of the way over to Sherlock's side of the cab. He nuzzled his face right into Sherlock's neck sniffing and inhaling as much of the delicious aroma as he could. "Oh, I don't care. Shut up and let me just smell."

Sherlock chuckled and put an arm around John's shoulders allowing him to press himself right up into Sherlock's lean body. He couldn't have asked for a better result from his prototype "love potion" than having John – his John- a quivering mess for him. But then, he'd formulated it specifically for John Watson.

"It's all right, John," Sherlock said low directly into his ear. It sent a shiver all through the doctor. Sherlock could feel John shaking with the need to get closer, to breathe more scent. He couldn't get enough.

Then, he actually began to whine, making a small needy sound.

The cabbie looked back and rolled his eyes. "Save it for home, boys. We've not got far to go."

"John," Sherlock said gently placing the heel of his hand on John's forehead and pushing back. John reared back, breathing hard and licking his lips. His pupils were dilated and his pulse raced in his neck. There was no doubt of his arousal. Sherlock traced a finger down John cheek and watched as John nuzzled it like a cat.

Oh, he couldn't wait to get John home. He had such plans….