If there was one thing that Rosario didn't get accused of, ever, it was being too approachable. Not that Cathal really meant it like that, guy was just being friendly, but still, she didn't know how to answer it. Fortunately, she didn't have to, because something else had caught Cathal's attention. She glanced down at the book she'd forgotten she was holding and surprise softened the awkward edges of her smile, lightening her expression. "Just getting into the freaky dark energy stuff. You like astronomy?"