There was really no reason for Nathaniel to stray all the way to the Circus before returning to Anita's house after his shift at Guilty Pleasures. Damian knows this, but decides not to pry for details that seem clear enough.

"Sex usually makes you a combination of sleepy and giddy, Nathaniel. Asher's bite would only add to that. Why do I sense unease instead?" Even as he asks the question, he knows, but perhaps it is better for Nathaniel to speak to him about it than stay silent.

Silence could really be a curse at times.