Because the prongs are solid steel and polished, insertion requires a significant amount of high-viscosity lubricant (silicone-based is recommended, as water-based evaporates too quickly). Users report that the initial insertion feels "cold" and "alien." Unlike a dilator, the YMD109 does not fill space immediately; instead, it creates points of pressure along the vaginal or anal walls.

Why does the YMD109 command such loyalty? Fetish theorists argue that the device bridges the gap between pain and clinical detachment . There is no leather, lace, or "kink aesthetic" here. The YMD109 is pure function.