There was a something about Sirius Black. Some little thing that lit up girls' eyes whenever they saw him. Some inexplicable thing that meant that no one could deny him what he wanted. Ever. James knew it was there: he saw many a professor fall prey to this mysterious something, and nice girls by the thousands. No one could say no to Sirius Black. No one wanted to.
One day James started noticing that this something wasn't just lighting up girls' eyes anymore. It seemed to have an effect on one boy's eyes, too. Remus's eyes lit up when Sirius smiled or spoke to him, and this was all very normal, exactly what Sirius did to all the girls' eyes. But sometimes this something in Padfoot made Remus's eyes cloud over with sadness, or anger. This only seemed to happen when Sirius was with someone else, anyone, if they were getting too close for the werewolf's liking.
No one else seemed to be noticing, or else they were just keeping quiet, like James had been doing. But James knew. He could see right through Moony and his "girlfriends" that never lasted more than a week. James just wished he could help, but Sirius seemed to be incurably straight.
As time passed, James thought he saw a slight change in his best friend. Sirius seemed to be becoming more aware of the look in Remus's eyes when he smiled. James saw Sirius begin to deliberately mess with Remus. Sirius would lean a little closer to Remus when they talked, "accidentally" touch him a time too many. James could swear that he even saw Sirius wink in Remus's general direction once or twice.
Now, James knew his friends better than to think that Padfoot was being serious, or to think that Remus was taking him seriously. Sirius had simply figured out Remus's secret and was having a little fun making him squirm. James had confronted Sirius about it and he had confirmed it. Remus, too, had stated that he knew Sirius was only joking.
And James believed them. Really, he did.
Well, he did until he walked into the dorm after being out with Lily one night, to find the two of them curled up in Remus's bed. It was the most innocent, sweetest thing James had ever seen, and James isn't the type to think of things as being sweet.
Remus was curled into a ball almost, and Sirius was behind him with his arm over the slighter boy's waist holding him as close as he possibly could. They were both fully clothed in pajamas, covers halfway up their stomachs. They were asleep and James didn't want them to become cold in the night, so he pushed up the covers. This action roused Remus a little, just enough so that he could talk without being really conscious.
"It's true, y'know, Sirius," he mumbled. "There really is a somethin' 'bout you. How d'you do it?" And with that he turned over and snuggled into Sirius's chest.
James smiled, happy his friends were happy, and went to his own bed.