Unexpected Sex... (Is the best)

Unexpected sex is amazing and I want to know if your ladies know why. My boyfriend and I were kind of annoyed with each other. We were discussing our relationship. Then out of no where he just started kissing me  at first I was like what's going on but it felt good so I kept going. It was so good and I don't understand why.  Have this happened to you do you get what I'm talking about ?