You call your drug dealer, figuring he will be easy to coerce.
Doug comes over reeking of weed. "Sup dude, why'd you call me over? Oh...hey dude...who's the chick?"
"I want to introduce you...but first...you need to take a shower, man, you reek! Here, use this shampoo."
You hand Doug the bottle and usher him in to the bathroom.
You hear the water running, then nothing. You wait for a moment and then finally knock. No answer. After some time you gingerly open the door to check what happened.
"Shit! Hey, a little privacy!" sputters the woman, who chokes on some smoke.
'Yep...that's definitely Doug...holy shit' you think to yourself. The genie really did give you a gender change shampoo.