Just use the line "I'm an off duty EMT" and have a stethoscope in your car.
When bfs come running out (which they will) take the stethoscope out and put it on the girls chest (when you're actually just playing with her boobs)
act like they need mouth to mouth "OMG, she stopped breathing!"
than start making out with them. (when they're sleeping/unconscious its hot)
Be ready for the bf to call you out, but also have your hand firmly gripping the taser in your back pocket.
Than, at the last second, unzip your pants and smack the gf in the face with your dick.
As the bf comes at you drop him with 50,000 volts to his nipples (if your aim is good like mine)
Than take girl to the spot so you can start taping.
And always remember to wear a mask in the tape if you plan on selling them.
This will keep Dateline NBC and the feds at bay.
Any more info on this can be found at my site
www.roofiesmakesleepinggirlshorny.com