Skinboat Journey
When banging a broad from behind, you keep switching back and forth from the Vagina and the Butthole. You give one thrust to the Vagina, pull out and quickly ram it in the Butthole once, pull out and jam your skinboat right back into the Vagina, and on and on.
Man this chick's 'gina and ass was so hot and inviting, that I had to take her on the Skinboat Journey.