Oh, fighting could definitely be hot -- he would have agreed with her on that one. But it wasn't hot with Riley because, honestly, Darin wasn't physically (or mentally, for that matter) attracted to her at all. Kind of funny, considering that Riley was an attractive person, but she just never had been to him.
He was perfectly okay with that. And it did make it easier to be partners, anyway. Better someone that he fought with, and had no sexual tension with, then someone he felt like pursuing, right? That could make things rather awkward.
Darin just grinned, though, when she got all sarcastic with him. He'd pretty much expected that.
"Don't worry, Riley," he told her, his own voice dripping with sarcasm as well. "If you're really nice, I might decide to put you on my calendar one of these days. I know how much you would love that."
As if he ever would. Not even if he couldn't get a date from anyone else, thanks anyway.