OK I kinda get it .. when they are discussing mutual friends - real life etc it's a little awkward and they disagree ... get them onto sex chat and the conversation just starts to flow .. sexually compatible, but that was all. Yeah, I can see why they clashed, and why he kept letting her back for the sex. He's trying to pull away I think, he gets pulled back into the sex before he knows what's going on and then it's a slippery slope.