Sherlock's steady hand lifted the gun, and he examined it with a far-away look in his heavy brown eyes. "Hm," He quipped, then turned the gun slowly towards his friend.

Watson eyed the barrel of the pistol warily. Fear twinkled in his eyes for just a moment, a moment the detective captured hungrily. Still stuck in a sort of daydreamy trance (as days of isolation will do), Sherlock reflected upon the control he currently held over the doctor; like this, he surely could have the situation any way he wanted. The young Watson had such a delectable bit of anxiousness about him, his heart flitting beneath those stifling layers like a pretty bird. Indeed, Watson was a pretty bird: male and lean though he was.

Sherlock allowed the moment to stretch into intensity. He saw sweat beginning to burn at the top of Watson's forehead. Then he said: "Do you like me?"

Letting go a lungful of air, likely out of annoyance, the doctor replied: "Holmes, I really think you're beginning to slip your sanity. How about a drink? A scotch and water maybe? You need to get out. Out of this room, out of that bloody window sill before you fall and break your spine…"

The 'click' of the gun being cocked shut Watson's mouth.

"You didn't answer my question, good friend," A lazy smirk crawled its way over Sherlock's features.

Watson looked at him, puzzled. "After all we've been through together, you're going to question my loyalty?"

"Loyalty…" Sherlock hissed. "Like a dog."

"Yes, like a dog, now put the fucking gun away!"

"Close the door." Sherlock interrupted.

Watson stiffened. "Why?"

"Because I want to discuss something important with you, my good man, so please, if you could be so kind: shut and lock the door." Sherlock lowered his brows and brought them up again, all the while keeping those dark eyes set on his partner, the gun raised and cocked and ready.

He watched Watson cautiously scale towards the door. He saw him shut and lock it. He watched him walk slowly back towards him, brow furrowed, confusion and annoyance on his features, and a little bit of hesitant fear too.

Silently he descended from the sill. Walked towards Watson, who stood uninformed but patient in the center of the room. "I'm doing an experiment." Sherlock said lowly, his steps deliberate and delicate, the gun still raised in one hand.

"And I suppose consent is not a requirement for participation as the guinea pig…"

Sherlock circled the man slowly, locked in an unbroken stare. "No, it is not. In fact, the experiment invariably performs better that way."

Watson's adam's apple bobbed. He lifted his neck warily as Sherlock came closer, the edge of the gun skimming close to his throat. "And what is your little experiment about?"

"Trust," Sherlock whispered.

"You don't feel that I trust you?"

"I've been locked in this room for six days," Sherlock snapped. "Now is not the time to be asking me stupid questions."

He watched the muzzle of the gun finally make contact with the naked white skin of Watson's throat. The man jerked nervously, gloved hands clenched, but kept his feet placed apart, back straight.

Sherlock put a knee between those legs, and then Watson's military training kicked in: an arm came down, the veteran's head ducking under, a whip of movement.

There was a scuffle, the sliding of feet. Watson's knuckles caught him in the lip, and he caught Watson against the wall, slamming his back into it hard, grabbing him by the collar by one hand. Then he put his knee back where he had intended it, rubbing intrusively between the thighs, and he put his face close to Watson's, and he breathed snakelike: "Stay still."

"What do you want?" Watson growled, blue eyes wide and piercing.

The hand that clenched Watson's collar into a wrinkled mess reached up and caught the fleshy curve of his chin. The gun pressed tightly into Watson's neck. "I want you to stop moving."

Heart racing, Watson turned his head to the side. "For god's sake, you could've paid a rent boy for this…"

"Shut up." The gun tilted, came up to Watson's cheek. He watched the bright blue eyes darting about unsurely. Then he pulled the gun back slowly, made some space between them, stood and said: "Get on your knees."

So the doctor did. Get on his knees, that is, on those perfect woven trousers that would surely need some sewing after this: he got on his knees with a tender delay and looked up with a sore, pouting redness in his face.