The effect we have on each other!

I don't understand how what just happened just happened!

So, Flatmate had said to me he wouldn't be online today as he was going to be snowed under with work, but next thing, there he is on msn. I'm at work he "should" be working and we just get into this very casual and extremely easy conversation. We were chatting for ages about fashion and shoes and we chatted about his work that he was suppose to be doing, and my stuf that I've been working on and we were just laughing around a lot. It felt so good.

Then it all went wrong, all of a sudden completely out of the blue, he's on the webcam wanking in front of me. I just let him, I was enjoying it but then just after about 5 minutes guilt poured over me. HE HAS A GIRLFRIEND AND IT'S NOT ME. I told him to stop. He did.

Then I was just like how did we get there, we were just in a normal conversation. He said it was the effect I have on him. I will admit in the past there has been times when I have intentionally wanted to have that effect on him, but today in our conversation was not one of those days. I just don't understand how we got there. In the end I told him to log off and do his work and I think he was a bit narked at me, I told him YOU HAVE A GIRLFRIEND and he said and doing this doesn't even bother me! Why do I, the single one out of the two of us, feel the guilt! It's not fair.

Anyway, now I am just completely thrown by all that. If anything he should have been annoyed at me after the commotion of last night.