I don't understand what is the big deal with this.
Your sleep shouldn't become interrupted. All guys can have a normal
erection while sleeping. Try to ignore the senses from your waist
down. Separate your mind from the other parts of your body. With a
little practice, you can sleep like a baby while your gf rides on
you.
You know what? I have a feeling that if you try to reject her next
time, she'll just say "Mind your own business, shut up and go to
sleep".
