One person, really? What about that other person in your car? They're not coming up to the room? Well, I hope you know I will watch you walk to your room, and the second I see that person walk through the door, I will call you and hassle you. And 99.9% of the time, you will be dumb enough to pick up the phone. And when I demand that your "visitor" come and check in with their ID, I will indeed call back repeatedly if they are not down here in the five minutes for which you asked. Oh yes, I will. I will continue until you pay. And in my human frailty, I will enjoy it, viewing this as my Holy Mission, my Crusade, and your punishment for lying to me.
So let me tell you again: I do not care what you are doing in your room—provided you are not damaging it. I do not care with whom you do things. As long as you check in all visitors and pay for the correct number of people in your room, I will not be bothered, and therefore I will have no cause to bother you. It's very simple.