An 18-year old girl and her 24-year old friend agree to go back to the condo of a 46-year old Saudi Shiek, after letting him buy them drinks in a "posh London club."
It doesn't take a genius to deduce what was agreed to.
She was "sleeping on his sofa" without underpants (or, apparently, a t-shirt), after he had sex with her companion in his bed. His semen was collected from inside the 18-year old's vagina, after he "fell on her" and apparently his erect penis penetrated her. Her "sleeping" position therefore must have been legs spread, without garments.
How are things in the Disney movie you're living in, Howard?