Speaking to a close friend apropos BDSM relationships, polyamory and how it was all going. He commented that he thought it was going to get complicated emotionally because "you are more likely to fall in love with someone who is giving you lots of orgasms." I'm not sure whether this says more about him or about his opinion of me, but decided that the point was worth giving a little thought to. It seems very cinematic, to me, and therefore totally false. Picture it: first fuck with a new partner, rolling over post-coitally in bed (assuming that quantities of bondage allow such a thing) and declaring in that chemical flush of prolactin to the brain that you are in love, truly in love. Intimate, absolutely; close, yes; happy and content, certainly. Love? Probably not.
The fact is that if love were solely linked to orgasm then I would be in love with myself to the exclusion of all others, with the possible exception of a wonderful young man I once knew when I was nineteen and our relationship consisted of fucking, lots. At the time, we did believe ourselves to be in love, and maybe it was love, of sorts, but I now think that it was perhaps more hormones. On the other hand, I've been in love with someone with whom I rarely fucked, which was a bone of contention, but never stopped me loving him.
I think that great sex makes you more pre-disposed to being or falling in love, but then I believe that to have good sex you need a connection in other ways - attractiveness, friendship, good old fashioned compatibility.