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The doctor was firmly ensconced in his armchair with the newspaper when he heard the door downstairs open. He grinned and turned a page. He'd ran a few errands after rearranging the sock index and then spent some time moving almost every piece of furniture in the flat. Not drastically‒he didn't rearrange the place, he just ensured everything was a little off-kilter. The sofa was closer to the window. The armchairs were further apart. The fridge, the bin, the kitchen table, the coffee table in front of the sofa, all of it was moved a few inches from where it had previously stood. He'd even rotated the skull on the mantle. He didn't touch too much of Sherlock's strewn items and case notes. He didn't want to cause real trouble or damage anything. He just wanted to be annoying, and he really hoped his efforts would pay off.

"Hey, Sherlock." John said as the detective strode into the flat through the kitchen.

"Hmm." Sherlock hummed in greeting and eyed the day's post on the counter, flipping through it. He stepped into the sitting room to hang his coat and John heard him freeze mid-step. He could practically feel the detective's eyes darting around the room, taking in details.

"John." He said, entering the room slowly.

"Hm?" John looked up, pretending he had no idea what could have possibly given Sherlock pause.

"Is something…" Sherlock pulled off his gloves one finger at a time, "different?"

John glanced around. There was the messy desk, the coffee table and pile of magazines. The fire crackling beside him. "No. What would be different?"

"Hm." Sherlock looked around some more, his expressive eyes narrowing and widening. John could almost see the calculations running through his brain, very aware that something was wrong and yet nothing was wrong at all. Sherlock finally hummed in his throat and hung his coat near the door before heading back to the kitchen. John heard him freeze again in the doorway and he couldn't help the huge shit-eating grin that crossed his face. Sherlock had noticed alright, he'd noticed more than John had hoped. Quickly schooling his features, he put the paper down and grabbed his empty mug.

"Mrs. Hudson was here earlier." John said, walking past the still figure of his friend and going to the coffeepot. "She brought up some odds and ends from the café if you're interested."

"Did she." Sherlock sounded decidedly suspicious and John had to try really hard not to laugh. You're a grown man for fuck's sake‒you should not be giggling like a schoolboy playing a prank on the headmaster! That's what it felt like though. Sherlock was always so aware and so sure of himself. It felt nice to finally get the detective even a millimeter outside his comfort zone.

John poured some coffee into his mug. "Yes, she did. What's gotten into you?" John asked, forcing himself to look at the man. "Did everything go okay at the lab?"

"Yes." Finally he seemed to snap out of it. "Fine." He strode towards his room.

"Do you want Chinese or Angelo's for dinner?" John called after him. He braced himself, waiting for Sherlock to discover the sock index and go ballistic.

"Angelo's!" Came the reply.

"Angelo's it is." John said to himself. There was no forthcoming sock explosion and John relaxed. It would actually be better if he found out tomorrow, John just hoped he'd be around to see it.

Sherlock was bringing his clean laundry to his bedroom later that evening. The flat was quiet and dark. John had gone up to bed a couple hours ago, as he had work early the next day. Sherlock dumped the clothes on his bed. It wasn't much, just some socks and underwear. His shirts and trousers were dry-clean only, so his washing loads tended to be small. He paired his socks just so and then pulled open his wardrobe, humming a Bach sonata vaguely to himself as he opened the sock drawer. The mismatched mess that greeted him was startling. Oh John…he stared down at the disheveled socks, smirking slightly to himself at John's method of retaliation. It was surprisingly subtle, not like a pile of intestines under a mattress. Sherlock found himself admiring it, even if it was annoying. He tidied the drawer in a few easy movements and closed it up again.

Challenge accepted.

He wandered back out into the kitchen, wondering what he could do. How could he exact revenge on the good doctor? There were always experiments, but that's what had started this whole thing. No, something else, something…Sherlock peered around, then his gaze zeroed in on the box of tea left out on the counter and he snickered.

Sherlock knew how fond John was of his tea and coffee. Every morning, before doing anything else, he would make himself a cup of one or the other. The coffee he had with milk and the tea with milk and sugar. If he wasn't working that day, he'd have a cup or seven throughout the day, and if he was working, he'd always make another cup of his evening blend when he got home. Yes, tea and coffee were consumed readily by both parties in the flat. Sherlock opened the cabinet. Two boxes of tea and a canister of coffee sat on the lowest shelf. The highest shelf in the cabinet was empty and even Sherlock had to stand on tiptoe to reach it. Grinning, he put the morning tea and the coffee on the high shelf, knowing that John would need to stand on a chair to reach it. The evening blend Sherlock hid under the sink. There. That should do it‒oh wait. He opened the fridge and took the milk out, placing it on the countertop, ensuring it would be spoiled by morning. True, he preferred milk in his tea as well, but in war, sacrifices had to be made. Now it was complete. He picked up a science journal and dropped onto the sofa with it, pleased with himself. He wished John a mental good morning and pushed the incident from his mind. No one touched his sock index without asking for a fight.

John staggered down the steps the next morning, groggy with sleep and hungry for caffeine. Sherlock was at his laptop, typing at the desk. A tall steaming mug of hot coffee was at his elbow.

"Mmm." John grumbled in greeting.

"Mm-hm." Sherlock hummed back. At this point in their friendship they had a shorthand with each other, and entire conversations were sometimes done in grunts and body language. He smiled at the screen when he heard John put water in the kettle and turn it on. The cabinet opened and he made a little sad noise when he saw there was no tea. The cabinet closed.

"Sherlock, you left the milk out!"

"Did I?" His voice was dry and distant.

"It's ruined!"

"Dear me." Sherlock continued typing.

The cabinet opened again as John looked through it once more. It closed. Some things were rummaged with and then Sherlock heard him wandering around the kitchen, opening other cabinets and pawing through contents. Sherlock enjoyed these noises thoroughly. It wasn't until John was standing in front of the tea cabinet again that Sherlock heard a very faint, "motherfucker" come out of his mouth. He glanced over. John was staring up at the beverages on the top shelf. He suppressed a laugh and sipped his coffee just as John spun around and gave him what Sherlock could feel was his Captain Watson glare. He drank the coffee for a long time and let out a satisfied "ah" when he put it back down. He typed a few more lines, still able to feel the doctor's gaze burning into his face. He could just see in the corner of his eye him clenching and opening his fists the way he did when he was annoyed or stressed. Sherlock couldn't resist. He looked at John, brows raised as if to say 'what of it?' John's glare softened and they exchanged a mutual nod. The game was on.

Sherlock smiled as John pointedly grabbed a kitchen chair and dropped it down next to the counter with a rattle-bang. He stomped up onto it and yanked the tea and coffee down, proceeding to make the angriest cup of tea in the world before hurrying back upstairs to get ready for work.

tbc…