The internal skeleton of a sex doll is fundamental for providing movement, stability, and a lifelike feel. Crafted with precision, these skeletons are typically made from durable metals like steel or aluminum, offering strength without excessive weight. The design process begins with detailed anatomical studies, ensuring the skeleton mimics human joint placement and mobility. Artisans carefully engineer joints that allow natural movement, such as bending elbows, knees, and neck rotations, while maintaining structural integrity. Customization is often incorporated, allowing for adjustable limbs or poseability to suit individual preferences. To facilitate smooth articulation, internal ball-and-socket joints or hinge mechanisms are used, often covered with soft silicone or TPE to conceal mechanical parts. The internal skeleton must also balance stability with flexibility; it should hold poses securely while allowing for repositioning without damage. During assembly, artisans meticulously attach the skeleton to the outer shell, ensuring seamless integration. The craftsmanship involved requires a combination of mechanical engineering and artistic sensibility, as the skeleton must be unobtrusive yet functional. This internal framework not only supports the doll’s aesthetic features but also enhances the overall experience, making poses more natural and the doll more durable over time.