You have actually written what happened to me in a Motel in Sanfrancisco, when I was in the States about 10 years ago.
I was in my room and knock came unexpectedly on my door. On opening it, there was a young black girl standing there, very attractive, with a very short skirt on, and showing plenty of boob.
She hastily apologised saying she must have got the wrong door. When she saw me really looking her up and down , she asked me if I was alone. and when I said yes, she offered me sex.
I admit I was pretty randy at the time, and she was so sexy that I said OK. I fucked her and then we showered together, and then she went on her way, I suspect to the next door along the passage. I didn't begrudge her the money as she said she was working to help pay her University fees.
Fred.