Once a month, John insisted on taking Sherlock out for a proper date. Apparently that entailed John paying for dinner despite the fact that they shared bank accounts, and Sherlock allowing John to open doors, pull back chairs, and take his coat for him. It didn't much matter to Sherlock, but it was important to John that he takes Sherlock out once in a while, so Sherlock cooperated. That evening John wouldn't say where they were going, instead he insisted that Sherlock do his best not to deduce the evening's plans, but to simply bring an interesting book.
This was enough to rouse Sherlock's curiosity but, true to his word, he didn't try to figure out where they were going. He'd dressed simply, in the purple button-down he knew John liked and his black slacks. John wore the blue jumper again as they'd yet to go shopping to replace his moth-eaten shirts.
When the cab arrived, John slid a piece of paper to the cabbie who immediately began driving a rather circuitous route, presumably to throw Sherlock off. They pulled up nearly fifteen minutes later outside a small café. John smiled at Sherlock's look of surprise. He stepped out of the cab, holding the door and assisting Sherlock out of the backseat before paying the cabbie and bidding him a good night. John took Sherlock by the hand and led him inside the cozy shop. Instead of booths or tables, the place was littered with large plush chairs, the sort Mycroft's study had when Sherlock had been a child, and small coffee tables to rest drinks on.
"I thought we could have a quiet night out, as our nights in never seem to be very quiet," John said with a small grin. He gestured for Sherlock to have a seat on the loveseat while John hopped in line to order.
The doctor returned a few minutes later to find Sherlock already immersed in his book. He gently set one mug of hot chocolate in front of Sherlock and then curled up next to his detective with his own mug folded gently between his hands. Almost absently Sherlock's arm slid around John and stroked his arm lightly. The hot chocolate vanished quickly, and John leaned his head softly on Sherlock's shoulder, reading drowsily, only catching the odd word on the detective's pages. He eventually drifted off to sleep with Sherlock's hand tracing idle patterns over his arm and wrist. Hours later, or perhaps only minutes, Sherlock stirred, waking John up.
"It's time to go, they're closing," Sherlock whispered, pulling a half-asleep John to his feet and helping him outside where he hailed a cab. Once they'd climbed in, John returned to his nap, leaning into Sherlock and curling closer as if Sherlock was his pillow. When the cab pulled up in front of 221B, Sherlock paid, knowing it would irritate John when he woke up fully, but not caring so long as he could keep John in this lovely sleepy state.
He helped his partner up the stairs to their room, guiding him gently into bed and removing his jumper and trousers before changing into his own pajamas and crawling beneath the covers. John instinctively nuzzled closer to Sherlock, pressing their bodies together as they drifted off to sleep.