Viennese oyster

Description: The complete fold is the pose: the receiving partner draws both legs back until the ankles cross behind their own head, self-locked, rotating the pelvis fully upward while the penetrating partner presses down over the top. This is an extreme-flexibility named position; the receiving spine rounds completely and the body compresses to roughly half its supine length, so the penetrating plank meets a compact, tilted target rather than a long one.

Variations: The legs can be pinned by the penetrating partner instead of self-locked behind the head, and the depth of the fold scales with the receiving partner's flexibility.

On camera: Rare outside flexibility-showcase scenes, it survives mostly in illustration. Overhead framing reads the fold best; side profile confirms the pelvic rotation.

AI design considerations: Place the receiving figure's crossed ankles beside the head, an arrangement that inverts normal limb logic, and verify every joint chain, since generators readily produce anatomically impossible legs here. The top figure's plank should clear the fold, not flatten it.