Remus looked over as Sirius related his chance lunchtime 'encounter' with Penny Clark, a dim but enormously breasted girl from Hufflepuff, for James and Peter. His face was alive with delight as he provided actions and sound effects to accompany his account.
Remus envied him; not for having groped Penny in a cupboard at lunchtime, or for having had half the girls in their year (and some from other years to boot), but for the fact that Sirius could have whoever he wanted, whenever he wanted, just like that.
There was only one person that Remus wanted and there was no way that he was ever going to get to canoodle with him down darkened corridors, much less act it out for his friends.