The lady clearly got on the cock of the sex-starved male! See with what pleasure and strength he fucks her, and besides when they started it was a bright day outside the window, and in the final shots of the video outside the window at night! How many hours in a row did he pull on the lady?
Staging is super, but the script could have been finished in a more interesting way, for example, either the awakened girlfriend would have thrown the friends out into the street, or even joined them and looking at her friend obliquely would have screwed her boyfriend much cooler than a mulatto!
What's her name after all?