Well... Luna expressed interest in Horus earlier. And Uriel told Wednesday that he had sometimes taken the form of a crow. And, just a while ago, Uriel flew with Horus. These all put together, I think it might be possible that Uriel went to fly in an alternative form (perhaps after Pesti and his break-up, to get rid of some of his anger and to sulk) and Luna then found a crow that felt "strange" the same way the hawk in the bar had.