After the full moon, Remus always got exhausted. The sheer toll of it tended to be a lot for him, he couldn't keep up with Sirius and James - too much energy required and he wasn't able to pull it off. It was easier to be with Peter around this time, he was a lot less intense, a lot less active and he could doze off against him and not be disturbed.

Which is what he'd done during lunch that day while waiting for Sirius and James to come, just nodded off against Peter quite content.

When he woke up, he was drooling on Peter's shoulder and swiftly pulled his head away. Whoops. "Er, sorry. Did I do it again?"