Fetishes are fetishes, while there are some "reason" behind them if you look through someones mind/history there's really no reason in trying to decipher it if you ask me.
It might be useful for your partner to understand you better(or viceversa). Your partner might be weirded out from an obssessive desire of yours to do that particular thing, but if it has a reasonable explanation that might help being accepted better rather than just being seen as a pervert.
I mean, you're probably still a pervert, but hey, at least you know why!
I would know since there is a certain thing I obsess over in my sexuality, but it's rare to find a person so stuck on doing one thing, most people have a fairly free sexual life.
edit: oh skipped a page, I'm late