Olivia Dunham was not as stoic as she tried to be. She was strong and independent and played her personal emotions close to the vest, sure. But if you really watched her, saw her for more than what she showed the world, and had an IQ of 190, you could eventually find the chinks in her armor. Reading people is what he did. And after the first time she'd blown that ability he'd been so confident in out of the water, he'd made sure to watch her far closer. And he was vain enough to say that it had paid off. There was little she could get buy him now and he was proud to admit that after nearly seven months of working together, she was starting to show him more on her own.

There was something odd he heard in her voice on the phone.

At first he was a little offended. What? He could only call her if there was something wrong? But he shrugged it off and thought that maybe she was having some quality time with her sister and niece and had just caught her at the wrong moment. She'd definitely relaxed, though, when he'd assured her there was no emergency. And then she'd hesitated and let out that slightly incredulous "oh" when he'd asked to talk to Rachel.

What was that about?

He'd pushed it aside during his conversation with the more bubbly Dunham, but stared at his phone as soon as he'd hung up with her. It'd almost sounded like Olivia was…not hurt, but maybe a bit indignant that he'd not called to talk to her. It was so quick though, and so small, he could hardly be sure. Had Rachel not told her about their night at the bar? She hadn't said anything about it and he hadn't thought to. It had been a long time since he'd felt the need to let anyone know what he was doing with his personal life. He'd decided to shrug it off and continue on his way.

Until the next day when he'd walked into the back office in the lab.

She'd been sitting there looking over reports trying to find a lead for near on two hours when he'd came in for a refill on his coffee. As often as he watched her, he'd never quite seen her stare at him quite so openly. As if she wanted to ask him something but stopped herself. Well he couldn't let that go. She tried to brush off her curiosity but back tracked almost immediately. It came out more as an accusation than a question until she softened it with slight concern. That caught his interest, but he decided to bide his time to test the waters.

"So you two are friends now?"

Gotcha. She'd tried to hide it with a teasing tone, but there was definitely something forced about it. That and all of the other little clues he'd gotten from her confirmed it in his mind. She was jealous. He'd never seen her colored that way before, but there was no denying it. Olivia Dunham was jealous that he's been hanging out with her sister. His heart rate picked up and he felt himself smiling before he could stop himself. The implications of what that might mean sent the warmth of affection and pleasure diffusing though his body. Well this was interesting.

"Does that bother you?"

He was teasing. Poking at her to admit what he'd already figured out. Her voice said one thing, but her eyes, still focused on him, were hardly even guarded. He couldn't keep his grin under control and used his refreshed coffee to try and keep him from laughing in near glee. Charlie's call signaled that they were back on the case, but this was definitely information he would be filing away for later.

He hoped Rachel wouldn't take it too hard when he told her they wouldn't be hanging out just the two of them anymore.