Is it normal to smell your ass while you masturbate

Emabarrased to say that as long as I can remember masturbating i've liked the smell of my ass. I don't know when this started but the enjoyment of it has increased over the years. I would use my fingers of my left hand and rub my ass and smell them while masturbating. This would make the turn on much greater. Discusting as this sounds I would many times not wash my ass so that the smell would be more intense thus creating a greater sexual thrill. What is it that is bascically dirty that turns me on and makes me more horny. Do other people do this. Is it normal. Im a professional and not some sexual creep. Ive been married and Ive enjoyed her ass smell, lol, but not as much as my own. My wife would notice that I didn't change my underwear sometimes. I would do this because it would turn me on to get as much of my ass smell on my underwear as possible. Am i sick or is this attraction to my ass smell nornal. Im very curious to know do other men and women smell their ass while they masturbate or any time for that matter. Thanks