Thank God, I've finally gotten some sleep! I got the idea for this from a Tumblr post. I'm a big Johnlock shipper, as I'm sure you'll be able to tell.
John stormed up the stairs, shopping bags hitting his legs.
Soft violin music floated down, and John emerged to see Sherlock dressed in his classic black suit and black coat. His purple shirt had stains on it, surely from some experiment, and he was barefoot.
"Ah, you got the milk. Than-"
Sherlock was cut off by John, whose blue eyes were full of fire.
"God Sherlock, you are thick for such a genius!" he shouted, throwing the bags onto the couch. Sherlock was immediately on the defensive.
"How am I thick?" he asked, setting his violin down carefully. John rolled his eyes, clearly agitated, his feet planted firmly on the ground.
"Deduce this!" John stood on his tiptoes (God, he hated how short he was sometimes), wound a hand roughly in Sherlock's dark, curly hair, pulled his head down to meet his and crashed his lips into Sherlock's.