They were comfortable and having a fun, if so far modestly tame, game of truth or dare. The oldie but goodie never had a reason to be shunned. Sirius was thirty, by two counts, but the big three oh wasn't going to make him suddenly grow up a lot more and stop having fun. He was plenty grown up. Sure he let loose here in some ways he wouldn't back home. Naked at a ball wasn't something a budding politician could get away with, even him. But Sirius hadn't ever wanted to do that there anyway. Here, someone else had the power to do that without needing permission whenever they wanted. Sure Gamma wasn't the sort to do that. But his point stood. It changed social norms. Anyway, he was waiting to hear about his tattoo.
Resting his elbow near his knee, Sirius leaned forward a bit, resting his chin on his hand, and looking up at Moony, just looking and not saying anything and inviting more and more of an answer. "Mmhmm," Sirius agreed, but he kept looking at Remus, like he fully expected the man to say more. Sirius did. So he just kept looking and waiting expectantly.