He cocks his head to the side, just a bit in that way he does. With the name Ioun still floating around his mind, that is a particularly interesting bit of information.

"You slept just fine with me for quite a while." Is he saying that to argue, verify, or just make Zerxus uncomfortable and redirect him a bit? Yes. Any or all of those. While still in bed with him, watching Zerxus' hair get wilder and wilder as it dries.

They should just get up soon. He can turn Zerxus loose in the library to entertain himself while Bruce... investigates.