Elliot, in general, had no social life. When he wasn't at work, he was in the CORE labs toying around with a project. People generally didn't warm to him; Ana was a rare exception, eccentric enough on her own that she could handle the mood swings and merciless pursuit of knowledge.
So, Rebecca's invitation had caught him a bit by surprise. She wanted to meet for a meal? He couldn't see a rational reason, unless it was to talk shop. Intellectually, he was aware that he had nice - if somewhat creepy - features, but that wasn't the same as feeling it. He hadn't been on a date in years. He wasn't even certain of the protocol.
He'd wait it out and see. Presume business, but be prepared to pick up the tab.
When Elliot stepped into the restaurant - California's take on Mexican food - he was still in his work clothes. That meant a suit, button-up, but the tie had been shed in the car. This was not out of a concern for formal vs. casual, but rather because the knotted band of fabric was uncomfortable and he shed the thing any time an opportunity presented itself. He glanced around, looking for the telltale shock of red hair that he recalled from the journals.