When Aaron hired you, he wasn't sure how you would fit in with the rest of the team dynamics. The BAU was a special team and while they could make just about anybody work well within them, the team had to be perfect. Perfect in his eyes.

It took a little time for him to warm up to the idea of having a new agent around, having you around, but you made it hard not to like you. You were good with the team, molded well with them, found your place quicker within the team than he'd expected. With him, however, it's like you took care of him. Always made sure there was a warm cup of coffee ready in the morning for him, making sure his printer was always full of paper, or bringing him snacks when he hadn't gotten up from his desk to stretch or eat.

It was little things like these over the course of several long months and harrowing cases that changed his feelings from new agent/strictly work to friendly to friends to something he couldn't quite place his finger on. It wasn't professional anymore, but it was a step above friendly, he knew that for sure. His feelings were confirmed when you, unasked he might add, brought him a cup of coffee on the plane and kept him civil company.

He asked you to stay back after debriefing the team and sending them home, asking you into his office. "I know you're tired, so I won't keep you long... How would you feel about possibly hanging out? After-after work, without the rest of the team... together?"