Ones into religious fetishes usually grew up in very religious homes and backgrounds. Religious blasphemy phone sex and the like is usually of interest only to ones from such backgrounds that held religion in high regard. As an atheist, I certainly have no interest in any baby Jesus butt plugs, yes they exist, or Virgin Mary vibrators, or bible or Budda or any of that kind of object that has been made into a sexual object.
One client I used to have was an English Vicar and used to love to have me swear over and over again, “Jesus fucking Christ”, and talk about how wicked he was and if only the parishioners knew about his interests, etc. A girl the other day I was chatting with said that she’d once masturbated in a religious confessional, and yes there was a priest in the adjoining one. Not sure if it was true or not, or if it was if the priest knew what she was up to, but many into this sort of fetish like that sort of forbidden encounter. Doing something so nonreligious in such a “sacred” place. Getting away with it.
It’s like they are doing the worst thing in the worst possible place and would everyone they know be horrified if they found out, what evil people they are. The priests and nuns who are supposedly celibate are also a target of fantasies for ones into this particular kink, the forbidden fruit at its most forbidden. That kind of thing arouses some like nothing else, it’s as if they are shaking their fist at God himself, say, “Look what I did where and with whom.”