I have a good friend from the service who spent 6 weeks in jail for just such an indulgence. She was in absolute ecstacy, until he pissed her off, of course. In true Emmy form, she ran half naked to the local police station, and cried rape. Fortunately for my friend, his attorney did enough digging to find out that she had done the EXACT same thing to 3 different guys in 3 different states. All charges were dropped.
Moral of the story: Get her fetish preferences in writing (yes, attorneys will write it up), or proceed with extreme caution. But you neednt take my word for it. Just ask my friends jailhouse rectum.
StD