For the last year I have wanted to be spanked during sex and have a tremendously pleasurable orgasm when I am. My partner is willing, although I don't think he realizes what a turn-on this is to me. I haven't told him exactly because I think there must be something wrong with me to feel this way. I think about being spanked all the time. I even try to spank myself.
Most people are more familiar with sexual obsessions about a particular person.
Depending upon your perspective, we call it love or stalking. You can ask for therapeutic help in investigating what it means to you, or you can allow yourself to explore the needs and its expression as you are doing, putting aide the notion that you are somehow sick. Although I have a live-in girlfriend, I enjoy soloing it once in awhile. While doing, so I often finger myself in the butt, first putting a well-lubed condom on my finger. Recently I tried a carrot, similarly sheathed for greater penetration.