Hand

"Very good, sir," Alice types your selection into her PC. "Now just two more questions for you. We have a few options for your anus that may help you relax or produce more ejaculate. I'll review them quickly for you."

"There's nothing, of course. Our attendants won't go near your back door if you don't wish. You can choose digital rectal insertion, where our attendant will stimulate your prostate with her finger, or our attendant can use her mouth and perform analingus. Finally, we have a mechanized dildo that can perform automated anal sex on you while you're milked."