Flicking through his copy of advanced potion-making, John wondered yet again where the hell Sherlock was. He glanced around the lamp-lit library for the hundredth time, searching the shadows for the familiar angular figure with the messy hair. Looking out of the snow encrusted window into the darkness, he saw his own pale reflection peering tiredly back at him, his hair was sticking up, courtesy of the many times he had run his hands through it this evening and the bags under his eyes were massive and shadowy. He looked a mess. Trying to steer his thoughts away from the lovely, warm bed waiting for him upstairs he picked up his quill again and re-read his last sentence: Therefore, without pomegranate juice the frogs eyes do not infuse correctly with… He had completely lost his train of thought, why was he so tired? It was only a Tuesday; the thought of three more days like this made him want to curl up under the table and curse everyone who came near. Pomegranate juice…. What about it? He'd just written a foot and a half about its properties, he was on the conclusion - that was good at least. All he needed to do was a couple more sentences then he would be free to go to bed, but for the life of him he couldn't seem to get his brain to focus.

'Powdered ginger-root.'

'Wha…what?' John gasped, almost falling out of his chair in shock. 'Sherlock! Oh, where have you been?'. He rubbed his face and ran his fingers through his hair yet again, trying to blink the tiredness from his eyes.

'I was busy. You look dreadful,' the pale Ravenclaw commented drily, pulling John's essay toward him and scribbling in the last few lines. John looked at him in shock,

'Why are you doing that?' he gasped. Sherlock cocked an eyebrow at him.

'Because it's fairly obvious you're not going to get it finished tonight and in an estimated, oh… five minutes you're going to be fast asleep no matter where you are.'

'But my writing. It'll be different and you know what McGonagall's like.'

'John. Copying your handwriting is child's play. And god knows how many times I've done it before.'

John gazed at him blearily, his sleep deprived brain processing this slowly.

'You...you've…of course you have,' he muttered, trying not to think about the implications of this. 'Well…yeah. Thanks, I don't know why I'm so tired.'

'Most likely because it is five to midnight and your usual time to bed is about nine o'clock.'

'Oh Hell! I didn't realise it was so late,' John moaned, a part of him did the thinking required to wonder how Sherlock knew what time he went to bed even though they were in different houses.

'Evidently,' muttered Sherlock, handing him back his finished essay.

'I've got to get to bed then…' yawned John. 'I'll see you in the morning if I ever wake up.' Scooping up his books, parchment, quill and ink, John stumbled off toward the library entrance. Sherlock followed him quietly, a hand on his back steadying the yawning blonde.

Sherlock supported him all the way to the Gryffindor common room, there he helped the exhausted boy through the portrait hole and whispering a goodnight, disappeared in a swirl of robes toward the Ravenclaw tower. The show of thoughtfulness had surprised Sherlock; trying to tell himself he had just been fulfilling his job as a friend he glowered to himself all the way to his dormitory. Sentiment. Not good. It seemed John was making himself into an exception. Maybe, thought Sherlock, he could be; he could be the exception.