The Dexter theme sounds fun....but I bet you'd have an easier time finding a multi if you were open to someone else shooting it.   I know that my husband prefers for me to work with a female photographer.   I know that that's not what you want, so I'm not trying to change your mind...just give you peace of mind about why no one is taking you up on it.   I mean the line of "hey....come get naked and restrained serial killer style" is a bit much to swallow if you haven't met the person before 

Totally understand @chefbeth its like an invitation to a horror film I would be weary too lol