Quick little story. Part of the 'Crack in the Door' series along with 'Of Spying and Storms'. Set in OotP.

Of Firelight and Firewhisky

Sirius Black knew lust like the back of his hand.

And what he saw before him was so much more than lust.

He had only gotten up from bed for a glass of water – which had quickly turned into a glass of firewhisky – when he happened upon the glow of a burning fireplace coming from inside the library. It was far too late for Remus to be up; heaven knows the poor bugger was probably tucked in bed with a cup of hot chocolate no later than eight. Expecting to see Kreacher stowing away smuggled heirlooms in secret hiding places, he had peered through the gap in the slightly open door.

He had never been averse to a bit of healthy spying, but what he saw made him feel like an intruder through and through.

Remus evidently hadn't been in bed by eight, because he was very much awake. And very much wrapped around Nymphadora Tonks; Sirius' cousin.

Sirius watched as Remus concentrated intently on a dusty looking book, absent-mindedly tangling his fingers into Tonks' hair. She was sound asleep, curled against Remus in a safe cocoon of blanket on the old loveseat. What surprised Sirius most was the ease on his best friend's face. Never would he imagine a situation where Remus could be pressed against a young witch as attractive as Tonks and look completely comfortable. Shouldn't he be looking extremely nervous? Shouldn't he be acting like the Remus that Sirius had known from school? Shouldn't he be doing something other than reading peacefully?

Sirius waited for the sweaty palms or the nervous cough that would indicate that he was indeed looking at Remus Lupin, but nothing of the sort happened. And Sirius realised that somehow his twelve-year delayed perception of his best friend had not yet caught up to the present. Because he was looking at an adult, and adult Remus was evidently as cool as a cucumber around pretty witches.

He watched as Remus' eyes travelled the length of the page and back again, the firelight filling the room with warmth and soft light. It lingered against the features of the room's occupants, casting shadows in the hollows of their eyes and glowing against the colours in their hair.

Tonks stirred a little. "Remus?" she muttered.

Eyes still fixed on the book, Remus gave a noncommittal hum in question. His hand stilled in her hair as she detached herself from the blanket that she had become wound in, and draped it over the both of them. Remus smiled against the top of her head as her breathing evened out once again and she fell back to sleep.

It was that look that made Sirius ache a little in memory of what it felt like to be in love; full of comfort and adoration. It had been so long since he had been able to feel love for a woman. He knew lust so well; he felt it on a daily basis, but what he saw before him surpassed love, existing on some higher plane. A love and respect that was pure; and Sirius had no doubt that it was pure, because Tonks and Remus had known each other for little over a month, and this was Remus for Merlin's sake.

When Remus put down the book and rested his cheek against the pink coif of Tonks' hair, Sirius decided that he shouldn't spy anymore, and mused that he had never foreseen such an unlikely alliance. Who would have guessed? No one, really. Nor would they believe him if he told them. But seeing what he had just witnessed, there was no mistaking it.

Remus had fallen for Nymphadora Tonks, and she for him. But they were in a war, and love was always the first casualty.

Sirius downed his firewhisky and tried with all his might not to think of James and Lily Potter.

There we have it. Please review and tell me your thoughts. This series will have more installments soon!