Rape - “The penetration, no matter how slight, of the vagina or anus with any body part or object, or oral penetration by a sex organ of another person, without the consent of the victim.”
Sexual assault and rape are often the same thing.
I'm disgusted at some of the replies so far.
Just because a woman agrees to let you come home with her and agrees to let you sleep in the same bed, DOES NOT mean you can 'try it on' and see if you can change her mind if she's said "No sex, I want to sleep".