Sherlock and John have an obvious height difference. Sherlock is 6 feet tall, taller with certain shoes on, and John is barely 5'7'' on a good day. It didn't often bother John, he did like that Sherlock was taller. And Sherlock liked to have that obvious sense of control over John, feeling taller made him feel like the boss, even though John is almost five years older than he.
Every once in a while, John would have trouble reaching for things that Sherlock purposefully put in the high shelves, and John would get huffy and angry and call Sherlock childish while asking his assistance to retrieve said item.
"Sherlock!" John would call into the living room, where Sherlock was hacking away at his keyboard, "Sherlock, you overgrown child, come help me!"
"Do what?"
John would mumble under his breath, "Get a mug off the top shelf."
"What? I couldn't hear you."
"Come get this fucking mug off the top shelf!" John yelled at his beloved Sherlock.
Sherlock laughed. He would laugh for as long as it took John to punch him or pinch him to get him to stop. Sherlock would finally get off the floor, from laughing so hard, and go to the kitchen to help John.
"It's not funny, Sherlock. It hurts my feelings, and-"
"I'm sorry, John, I just try to have some fun with you. You're so cute when you're huffy and angry with me."
"I'm not trying to be cute, Sherlock, I'm trying to have tea and you deprive me."
Sherlock reached high into the cupboard, making his t-shirt ride up over his belly button, and John loved that part. He stared at Sherlock's stomach, a part of Sherlock he loved. His hip bones stuck out just enough to make a small space between his pants and his skin when he sucked in, but when he was relaxed there was enough muscle to make the v-shape at his lower abdomen. John loved it.
This could be an arrangement John could get used to; Sherlock hiding his mugs in a top shelf, Sherlock's laugh when he knew he had gotten John, John receiving a free view of Sherlock's wonderful stomach, and all the kisses John received after Sherlock knew he maybe pushed John too far.