John's only appointment for the day had just called in to cancel, and he didn't hesitate to shed his lab coat and roll up his sleeves. Even his basement office in 221-C was hot. He eyed the door to Sherlock's lab hesitantly. It had been quiet, almost too quiet, for a couple of hours, and John was trying not to get too concerned. John checked his watch, and decided it was time for a walk in the cool breeze in Regent's Park. Preferably with an ice lolly. Jack was sleeping over at his friend Rhys' house, and Sherlock's phone had been silent all day.

Deciding to make a move, John crossed to Sherlock's lab and knocked. The tinkling sound of breaking glass came from within, followed by Sherlock cursing under his breath. "Yes, what?" Sherlock finally snapped.

"It's bloody hot in here, I'm going to the park," John said, ignoring Sherlock's tone.

"Fine," Sherlock muttered. John waited at the door, grinning as he heard Sherlock's approaching footsteps. The door flew open and Sherlock emerged, his shirt open an extra button and his sleeves rolled up to the elbows. "It's miserable, I can scarcely concentrate on my experiments. I'm coming along, I believe I could use the fresh air."

John felt a familiar and unwanted twist in his stomach at the flush on Sherlock's cheeks, a couple of his curls damp and flattened against his temples. Sweat had beaded on Sherlock's upper lip, and he pulled out a handkerchief to dab it away. John felt his ears burn and he looked away. John crossed over to the small water cooler in the corner and filled a little paper cup, draining it in one go.

Sherlock folded his handkerchief and watched John, frowning. "I thought we were going? Are you alright?"

John nodded, composing himself. "Right. This heat , it's…getting to me, I suppose."

Sherlock levelled him with an unreadable expression for a moment before something in his gaze shifted. With a smirk, Sherlock pulled open the door and led the way outside. John was scared to consider what Sherlock was smirking about, but he followed him all the same.

"I have a proposition."

John, who was focusing on his lemon ice lolly and decidedly not looking at Sherlock as he ate his ice cream, made a noncommittal noise. "You are filled with propositions. What is it this time?"

Sherlock finished off his small cone, watching John carefully. "I don't think I'll tell you. You'll just say no."

"Then why bring it up at all?" John asked, tossing his stick in a bin along the path back to Baker Street.

Sherlock didn't respond right away. He reached over and took John's hand in his. A calculated manoeuvre. "I just want to offer you a bit of forewarning. I want to try something, and I want you to allow me to try. If you are uncomfortable, or I am uncomfortable, we will stop. But I want to try a series of experiments for which I would like for you to maintain an open mind. I will explain further when we return home."

John tried to work out what exactly Sherlock was talking about, but the careful neutrality of his facial expression gave no clues. "That sounds ominous," he finally replied, not sure what else to say.

Sherlock pushed his hair back off his forehead. "Nothing of the sort, I can assure you."

John didn't feel assured.

When they arrived home, John threw open all of the windows in the flat, trying to coax in a breeze. Sherlock disappeared upstairs, and John wasn't exactly sure what that meant. Instead of thinking too much about it, John got himself a cold beer and opened his laptop, checking his blog for comments. There were just a few drunken comments from Harry inquiring about Jack, but nothing else.

"John, I need your assistance," Sherlock called down the stairs, and John sighed as he shut down his computer. He trudged up the stairs, beer in hand, and he stopped in the doorway. Sherlock has drawn the curtains and he was standing at the foot of the bed, his feet uncharacteristically bare. "Listen to me," Sherlock toned, his voice low.

"What are you doing?" John asked, surprised by how weak his voice sounded. "What are you doing, Sherlock?"

"I want you to undress me," Sherlock said, the definition of calm. "I want you to touch me, and I don't want you to feel ashamed by your reactions to me."

John felt sick and hot, and he shook his head. "We can't do that, Sherlock. We can't open that…we can't open that door, because I'm afraid I can't close it back. We've talked about this."

Sherlock looked like he wanted to approach him, but was restraining himself. He took a slow breath and slipped his hands in his pockets. "I'm thought about this, John. Extensively. I've done little else this week. I would do anything for you, and I want you to be happy, and this is something that I can do for you. I'm not opposed to sex. I have suffered no past trauma. I'm just not interested. And you are. And I want very much to find a way to have a sexual relationship with you that doesn't require my own arousal. So I've come up with a few ideas, a series of experiments I would like to perform. And you are the only person in my life that I have ever trusted enough to want to…to try with."

John's throat went dry, and he took a long drink of his beer before putting his bottle down. "You're a virgin."

"I am," Sherlock replied without a trace of embarrassment. "Everyone assumes that because I was an abuser of recreational drugs that I was more careless in other aspects of my body. But I can assure you, I was always very careful and only ever used drugs in very controlled environments. I always retained perfect control of my body, and I trust you to allow me to retain that control."

"Yeah, of course," John said, unable to stop himself from approaching Sherlock, lifting a hand to slip this fingers though Sherlock's sweat-damp curls. Sherlock closed his eyes, smiling fondly at the touch. "Sherlock, I will feel like I am taking advantage of you. It's no fun for me if you don't…want it."

Sherlock leaned in to John's hand, and when he spoke, his voice was dangerously close to a purr. "I want to have your attention. All of it. I want you to look at me, never stop looking at me, and I want you to touch me. Hold me. I don't want you to look at anyone else, touch anyone else, and I want you to be happy. So I am willing to do something for you, make concessions for you, so that you can fulfil my needs and I can fulfil yours."

John slid his hand down to Sherlock's neck, feeling his pulse against his fingertips. John could feel the beginnings of arousal stirring in his groin, and he could smell Sherlock's warm skin. "I don't know what you want me to say," he finally said, sliding his thumb over Sherlock's earlobe.

"I don't want you to say anything," Sherlock said, lowering his mouth to John's. He slid his tongue over John's lips before sucking John's bottom lip between his own. He kissed down John's chin, down his neck, before burying his nose in the hollow of John's collarbone. "I want you to undress me first, then we may begin."

John's fingers tightened around Sherlock's hip.