Sherlock ran, rather enthusiastically, into the flat. He slid onto the carpet, momentarily losing his balance for a split second before speaking, "John. We must leave, now."
John looked up expectantly, excited about whatever he would be needed for, "What is it? Another case? A murder? Kidnapping?"
"Not exactly," Sherlock said, "Just, come with me to the ice cream parlour, it's for an experiment."
John turned from expectant to curious in a fraction of a second, "Ice cream parlour? What kind of experiment can be done at an ice cream parlour? How many scoops of vanilla you can eat before you get sick?"
Sherlock simply shrugged in response before trotting over to John, grabbing him by the hand, and racing out the door. "It'll be fun, I promise," he assured, running down the street, and turning a sharp corner as John yelled for him to slow down, stop, please. He complied, slowing his stride as they reached the shop and then stepped inside.
The small bell on the door dinged as it opened and then shut behind the two men, who were still hand-in-hand. John detached himself from the detective and sat gingerly in one of the small, white metal chairs. He played with his thumbs while Sherlock read the menu, as well as the now-uncomfortable cashier, and ordered too much ice cream.
"Here we are," he said, placing the large bowl of chocolate, vanilla, and strawberry ice cream adorned with too much syrup and two delicate cherries on top of the wobbly table and sat down opposite the doctor. He handed John a bright green plastic spoon and dug into the vanilla with his own, then brought it to his companion's mouth.
John eyed it cautiously, then took the bite as it was offered, smiling lightly at the detective after he swallowed, "Mm, not bad," he said, picking one of the cherries off the top, removing the stem, and popping it into his mouth.
Sherlock watched John adoringly, scraping more ice cream onto the spoon and then placing it into his own mouth, shrugging, "It really isn't that bad," he said with his mouth full before swiping the residual ice cream onto John's perfect nose.
John scrunched his face up as the lukewarm cream was wiped onto him, "What'd you do that for?" he asked, rubbing it off of himself and taking another bite out of the bowl.
Sherlock shrugged again, "Think of it as a mini experiment. Trying to find out how hedgehogs react to various substances being placed on them," he explained with a light chuckle, spooning more ice cream into his mouth.
"Ha ha, very funny," John replied. he shoveled more strawberry onto his spoon, then into his mouth, shuddering a little when the cold hit his sensitive teeth.
The two men sat in the shop, feeding themselves, and feeding one another until they had to loosen their belts and waddle out the door with a light thanks to cashier. They lethargically shuffled back to 221B, hand in hand through the dusk, mumbling half-words at each other before pushing each other up the stairs and into the flat.