It wasn't like Brennan was some nervous teenager when it came to sex. Sure she was a bit socially awkward, but she'd had boyfriends. And a lot of sex, she knew what she was doing. It was the only time she let herself not think and stop being logical. Because there, she could just do what she wanted to do, feel and touch and kiss and lick and anything else that came up to her mind. It was actually rather easy to turn off her brain and give in to completely what was happening there in that moment. He was touching her, and it sent a shiver up her spine, knowing that he was touching the most intimate parts of her.
She nipped on his bottom lip, her hands wandering down to his hips and though she teased the elastic of his boxers, she didn't quite slide her hand inside just yet. She wanted to feel his hips, so she pulled them down just enough. Some part of her was probably amused that he was already hard, but she supposed she had been teasing him quite a bit before, so this was only natural. At least she knew he was ready.
Her back arched up under him and her hips kind of rocked since she was feeling him between her legs and she was probably making a wet spot on the front of his boxers with the way she was rubbing against him. But god it was good to have friction and she really didn't realize what she was doing but she really didn't want to stop.