Guys and girls lube up with slimy nuru gel (methylcellulose / Natrasol type lotion) and massage them with their naked bodies. Then very happy endings...

Women's wrestling site, with some oil involved.

It's a familiar scenario: a girl sees a green lawn, only to find it's a deep quicksand. But what if she knew it was a quicksand? Did that stop her? Tiny steps on the waving layer of grass and feels a thick peat bog beneath. She continues to step deeper, her feet breaking through the grass that carpets the surface. Once deep enough, Tiny continues to sink, waist-deep, then chest-deep, shoulder-deep, and so on. She barely resists, and for a moment even seems to enjoy it. Tiny only becomes a little alarmed when the muddy mass reaches her head. She realizes resistance is futile and allows herself to be sucked in completely. In the bonus video, Tiny dives, emerges and escapes. Note: This is a fantasy scene intended to entertain fans of women in peril. Nobody was harmed during the filming of this scene.