(Hmmmm I can have a go! I haven’t written Sheriarty in aaaages! Thank you for the prompt - hope you like it!)
Jim lay in his bed, a cigarette between his lips, the smoke curling and undulating up towards the ceiling. The window was slightly open, and the cool night air felt good on his bare chest. Sherlock was sleeping soundly next to him - the detective was curled up like a little cat, breathing softly and infrequently. It really was like watching a pet sleep - one second you think they’re dead, the next second they breathe and you’re relieved. Sherlock didn’t often sleep, but when he did, Jim liked to watch him. It was relaxing, seeing the erratic man be calmed by something as simple as sleep.
Jim took a long drag from his cigarette before stubbing it out in the ashtray on the bedside table. He paused for a second, letting the smoke out of his lungs in a long, slow stream, then swung his legs out of the bed and stood up. He didn’t want to sleep - his brain was too alive for something so mundane - and he didn’t want to watch Sherlock either. Instead, Jim crossed to the window and closed it, just for something to do. He ended up staring out at London, watching the tiny cars flash past with beams of light streaking behind them.
If he squinted, he could just about see Buckingham Palace, right over in the distance, along with Big Ben and the Eye. Following a random road, he eventually saw the Yard, then Hyde Park, then Baker Street, where he was confident in knowing that John Watson was sleeping soundly in his own bed. Jim smirked. He wondered if Sherlock missed his little toy. He doubted it.
Jim only looked at Baker Street for a second. He followed the road right towards his own block of flats, eventually ending up staring at his own face in the reflection of the window. For a moment, he didn’t recognise himself. He looked too happy, too positive to be Jim Moriarty. Moriarty was a cold, ruthless killer - a man who had killed his first victim at merely 13 years old, a man who had done untold things to be in his current position. But this was Jim staring back at him - the Jim that wanted to shed the Moriarty exterior and be someone he’d never been. A proper human being.
Jim whirled around to face Sherlock, who was still sleeping. He shook his head violently, trying to rid himself of those contaminating thoughts. He was Moriarty! He would always be Moriarty! That was his life, that was his purpose. To be a criminal, to devise schemes and plots, to be, as he was so often called, the Napoleon of Crime!
Jim paused. He knew that was his fate.
So why did it make him so sad?
Sherlock stirred under the covers. He rolled onto his back, blinking his grey eyes to get rid of the drowsiness. “Jim? Are you alright?”
"Fine." Jim snapped. He caught himself, took a slow breath, then replied normally with a smile: "I’m fine."