Rich hadn't really noticed her before, but it's hard to keep not noticing someone who is persistently staring at you.

He glances toward her. Looks away awkwardly when they make eye contact. Glances toward her again.

". . . Can I help you?" he asks cautiously.

(He doesn't have enough information about her interactions with the other Rich Brook to even try to pretend to be him, so he's not going to bother. It would be self-defeating.)