When a female places both hands firmly against the lower-side sections of her breasts and pushes them together in a repetitive motion. If motion is executed quickly enough, the sound of the breasts smacking together gives off a kissy kiss noise. Can also be done by males although slightly less attractive opposed to a woman practicing the art of the Seal Kiss.
George: Hey Tim! Did you see Jen give her twins the Seal Kisses?
Tim: Darnit I missed it whilst grabbing another Brewsky out of the cooler