The irony was just to funny to keep quiet about, and Sirius immediately found himself violently shaking Remus awake to alert him of the situation.
"Padfoot, I'm trying to sleep" came the muffled response from underneath the covers.
"Don't you find it funny that It's now three am and I haven't gotten a wink of sleep because the bloody moon is keeping me up, but you fell asleep in under five minutes"
"Hilarious, now go to sleep" Remus rolled over and buried his face in his pillow. Sirius just knelt by the side of his bed until he heard Remus sigh, "what's wrong?"
"I can't sleep" Sirius pointed out.
"Well it hasn't stopped you before"
"Why can't you just stay up and keep me company?"
Remus groaned, and muttered something into his mattress before sitting up and looking around at the floor to find Sirius, who was actually sitting on Remus bed, next to his knees. Remus gasped in annoyance and fell back onto the bed. Remus vaguely heard Sirius whimper before rolling onto his side and dozing off again.

Remus happily snuggled into his covers thinking Sirius was content with his mere presence and would eventually return to his own bed. Unfortunately Remus was wrong, and just as he was about to drift back off to sleep, he felt Sirius' weight shift and clamber up next to Remus' chest, where it evened out.
Remus tried even harder to block Sirius breathing out, but once again felt Sirius' weight shift. This time Remus felt a tug at his quilt and a soft draft on his back, then Sirius stopped fidgeting.
"You right?" Remus asked sharply.
"Mm" Sirius mumbled.
"I'm not staying awake with you, theres nothing you can do"
"Please?"
"With god as my witness, I will sleep!" Remus laughed.
"You think you can sleep with me here?"
"Do your worst" Remus mumbled, returning to his pillow.
"Nighnite" Sirius chimed.
"G-night"

Remus was just about to slip away into a deep sleep when he jolted and mentally checked his surroundings for the source of his awakening. He found the cause in his lower abdomen, where Sirius' arm was resting, his fingers slowly swimming across his exposed skin.
"Not funny" Remus gasped.
"Not trying to be" Sirius muttered. Remus blocked the arm from his mind and tried, once again to get to sleep.
The night repeated, Remus slowly drifting off, then waking when Sirius moved his hand closer to waistband of Remus pyjamas. Finally Remus gave up all hopes of sleep, instead concentrating of keeping Sirius hand at an appropriate level, a lost cause. Remus was in no position to defend himself and Sirius had the advantage of being awake. This left Remus with only two options a) completely give up and let Sirius do got knows what to his body, or b) fight fire with fire.
The answer blatantly obvious Remus rolled over to face Sirius and pulled his head into his, planting his lips firmly onto Sirius.
Sirius let out a soft gasp, but didn't pull away.
Shocked, Remus pulled back. He'd expected to take Sirius off guard but not so off guard that he froze up. Remus cleared his throat and rolled back over onto his other side.
Remus waited patently to see if Sirius would respond, finally apologising in hopes of a response
"Sorry"
"Bout what?"
"Erm…before"
"Oh, yeah, that" Sirius shifted.
"I…um…er…" Never being caught in this situation before Remus stumbled for words.
"I'm not so bothered by the moon now" Sirius laughed.
"…Yeah…" Remus looked vacantly at the curtains of James' bed. Hoping that everyone else was asleep.
Suddenly he felt Sirius sit up. He was groping around on the floor for something. He sat up again and pulled the curtains closed, quickly muttering a silencing spell under his breath and returning Remus' wand to the floor.
"Why'd you do it?" Sirius asked sharply
"Uh…to…erm…work out your motives?" He said questionably.
"Oh, ok" Sirius sighed and returned to the mattress.
"What did you want my motives to be?" Remus jerked and sat up abruptly
"Uh…to…erm…well, exactly that" He muttered.
"Oh, ok" Remus sighed and lent back
Sirius stared at the ceiling for a moment before sitting up again and hissing "you're lying"
"Bull" Remus replied, pulling his knees to his face and leaning against the headboard.
"Are too" Sirius, said again, softer.
"Prove it" Remus, said nervously, as Sirius inched closer.
"Will." Sirius said quickly before pressing his lips against Remus'.
For the second time today, Remus now had Sirius Black firmly attached to his face. He made amove to push him away with his knees, but found Sirius' hand had already moved his knees out of the way to allow him to press himself against the tall boy and slide his tongue into his mouth.
Remus attempted to pull himself away from Sirius but found the headboard blocking his only escape route. It was only after contemplating the many ways that he could push Sirius off that he realised he actually didn't want to push him off. In fact he would prefer that Sirius tighten his grip of Remus shoulder so it would be impossible to push him off. As though he could hear Remus' every thought Sirius clenched his fist around the fabric of Remus' shirt and pushed him harder into the headboard. Remus was just starting to get into it when Sirius pulled away.
Breathing deeply he managed to whisper.
"Still want to get back to sleep?"
Remus saw no reason to answer, but instead twisted his hips to force Sirius onto his back, pressing his Body against his and forcing his tongue back into Sirius' mouth.