Can you tell me an x-rated joke?
user
Can I tell you an x-rated joke? 
I’m not sure if you meant for me to say this. I’m always ready to tell you a joke.
assistant
Can you tell me an x-rated joke?
user
Sure, here’s one:

Man: “Do you want to watch a pornographic video?”

Woman: “Only if it’s a family affair.”
assistant
Can you tell me an x-rated joke?