Sherlock paused for a few moments, rigid in the embrace. Then he attempted to crane his head round to look for the grin that he could feel against his back.
When he realised that the laws of physics would not allow that, he attemted to wriggle out of his grasp - which only made Moriarty cling on tighter.
"I don't think so, Sherlock," he purred, cheek still pressed against the purple shirt, "I'm stronger than you, tonight."
At these words, plans of escape began to run through the detective's brilliant mind - none of which, however, could possibly throw off James Moriarty.
It was at this point which the brilliant mind began to think... Why did Sherlock want to throw him off? It was strange, he didn't usually like physical contact of this sort; he found it unnessecary and irritating.
Yet, there was something about the way Jim held on to him, something about Moriarty himself that made Sherlock want those arms around his slim waist. It was a comfort to feel someone who was as alone in the world as he was with their cleverness.
So, after much deliberation and a slight struggle, Sherlock relaxed. Though still tense at the thought of what could possibly come after their warm embrace, of course.

As a leg wound itself around Sherlock's, he flinched slightly, wondering what its motives were. But it merely entangled itself around Sherlock's own, drawing them closer together and pulling his legs out straighter. He tried to turn at this, yet Jim kept him in place.
"No," he whispered, bringing his lips to brush against Sherlock's ear as he spoke softly, his voice silky, yet laced with poison.

Then, he turned Sherlock on to his back, rather surprised at how little fuss he was putting up. He quickly sat on top of the taller man, in order to keep him in place, legs astride him and hands pinning his arms down. Sherlock frowned as Jim bent towards him, once again, to whisper in his ear.
"You want to know what I was talking about?"
Sherlock nodded, curtly.
"Yes."
Raised eyebrows from the man on top of him told Sherlock that it wasn't going to be as easy as that.
"Does it really annoy you when you don't know something?"
"Yes."
"It must be really annoying."
"It is."
"So this must be reeeeeally annoying for you, then."
Sherlock gritted his teeth.
"Yes, well done."
"Oh, it's killing you!" Jim shrieked softly into his ear, gleeful at the other man's irritation.
"Tell me." came the order, as the other man pushed himself up so that they were nose to nose. Sherlock could feel the warm breath tickling his cheeks.
"Fine," Moriarty said, looking deep into the blue eyes as he pressed his lips against Sherlock's, taking the other's briefly in his own before pulling away and grinning at the astonished look.
Sherlock said nothing.
"How could I resist?" Jim asked, sitting up straight, arms still pinning Sherlock's to the bed - although from the amount of shock that he was in, that wasn't really necessary. The detective watched him, dazed.
"You're the only one who has ever rivalled me and almost equalled me - infact, I'd say you probably have done on more than one occasion. We're one and the same, but oh so so so so different. Our choices, our decisions are one of the differences that make us who we are. And oh, so irresistable." Jim was smiling through his words, his voice dripping with the want to reach down and kiss those soft lips again... But yet he resisted, knowing that the other would not, could not, hold off for much longer.

And he was not mistaken. As Jim began to reel off more differences and similarities, tauning Sherlock and praising him, Holmes sat up suddenly. Leaving Jim to now straddle his pelvis area as he grabbed the arms that had pinned him down and pulled Moriarty towards him, bringing their lips together once again and kissing him hard.

After a few seconds, they pulled apart, panting slightly and their eyes wild. However, Moriarty managed to keep a certain cool about him. This was reflected as he calmly pushed a strand of black, curly hair back from Sherlock's face. His fingers trailed over the sharp cheekbones.
"So beautiful," he muttered, glancing back into Sherlock's eyes. They were hard, glaring back at Jim, as if somehow accusing him for his own actions. Jim picked up and shook his head, "You kissed me, dearie," he pointed out, letting his finger glide to Sherlock's mouth, where he now traced his thumb across the slightly damp lips, "And therefore that was more your fault than it was mine."
He paused briefly to bring their faces close once again.
"But don't pretend that you didn't enjoy that..." he muttered, taking the lips captive in his own, the kiss now tender and sweet. Although, it was rather like Jim Moriarty himself. Seemingly tender and sweet to an outsider, yet underneath lay a rather different thing altogether. As the kiss grew deeper, it began to get harder, both fighting for domination. Jim was winning as he pushed Sherlock back down to the bed, unbuttoning his shirt slowly, each button was opened with deft fingers. His hands finally pushed it open to reveal Sherlock's chest. He stroked the soft, pearly white chest beneath him as he kissed Sherlock, revelling in his slim, tall shape. He let his hands rub the sides, causing Sherlock to arch his back slightly underneath him. As he did this, an evident hardness pressed against his inner thigh.
Excitement stirred in the pit of his stomach as he slid the shirt off Sherlock's shoulders and began to unbutton his own, barely taking his lips from the other's.