Fetishes, everyone's got one. Some are common, some are pretty off the wall. And sometimes, you don't learn about your fetishes until something exposes you to it.
This is what happened with Prince Dusk Shine. Never before had he considered the possibility of him developing such a fetish, until he saw it in a romance novel. Now he has the task of trying to bring it up with his boyfriend while still uneasy about having it in the first place.