Aaron may not have lie detection, but he could tell she wasn't being truthful, or maybe he just liked to think it because he was pretty positive the idea would never have even crossed her mind if he had never brought it up in the first place.
And he was so under her skin. He could tell. It was so obvious. After all, she'd gone out and asked around about whether or not it was strange that she'd lived in NYC all her life and never ridden the subway. She wouldn't have had to ask if it wasn't bothering her. But he wasn't taking much pleasure in it for the moment. Mostly because he hadn't intended to get under her skin. So why should he care if it had happened, right?
He sucked in a sharp breath, "Maybe." That was an I-don't-really-believe-you-maybe. "But it would never have even crossed your mind if I hadn't ragged on you about it, and you know at least that's true."