Wounded and with broken Grace or not, Crowley could feel when Michael entered the bar. He turned over and looked at him, for a fraction of a second his eyes flared red and he saw a flash of the angel form. If circumstances were different, if Michael were in peak condition, if Crowley had access to his Hell, he'd be able to see more, but Crowley could see a flare of the blue in Michael's eyes and a hint of it in the vessel, not to mention a vague silhouette behind. A blink of the eyes later and Crowley was just looking at the vessel.
He didn't want to stare, so he didn't. That didn't mean he couldn't take Michael in when he wasn't looking at him. Michael might have found him familiar, but Crowley found Michael familiar as well, in different ways of course. There was that fraction of familiarity he got from Lucifer, the traces of pure Archangel that weren't corrupted by his Fall, then Crowley of course remembered Raphael from the good old Purgatory plot days with Castiel. And of course Gabriel. Crowley knew the general difference between angel and archangel, but there was still something different about Michael that gave him pause. It wasn't the fact that he was wounded, although perhaps it was. It just made him all the more curious. It made him wonder almost if Michael had brought a lingering fraction of the cage's magic with him. Perhaps that was what was keeping him from healing.
"A nightclub?" Crowley's brows lifted at that and he chuckled before he could stop himself. "Centuries ago, maybe. Who knows? It's still early." He smiled at the thought, head canting slightly. It did actually cross his mind when he first got here, funnily enough.
"So, I suppose you're wondering why I've called you here," Crowley said gently, thumb gently tracing along the edge of the glass. He didn't want to beat around the bush, and while he could have been cute and asked Michael how his day was at work, sweetie, he had too much on his mind and he looked too troubled to even bother schooling his expression.