Marshland Motorboat
A variation of the more common inter-cleavage motorboating, marshland motorboating consists of putting ones lips to a woman's exposed vagina, and simultaneously blowing and vigorously shaking one's head back and forth, thereby imitating that sound of small boat's engine.
Julie thinks we need to spice up our sex life, so tonight I think I'll give her a little of the old Marshland Motorboat.