Remus thought Sirius was looking shifty. Now that was a sight he was used to. It usually happened when Sirius was confessing to doing something not entirely right. But in this situation, Remus couldn't think of anything Sirius had done wrong. "Yes. That's the one I meant," he said, feeling a bit bewildered.
Remus had not known about Sirius' idea to get him drunk, of course. If he had, he would have politely excused himself and ran away to hide. It was embarassing enough the first time round. Remus rather thought he did atrocious things when he was drunk. But there was no way he could have known. Hence, he was still sitting there.