prone bone
A sex position where the receiving partner lies flat on their stomach (generally, only the stomach, crotch and maybe thighs need to be completely down flat on the surface) while being penetrated from behind.
另请参见
一种性交姿势，接受伴侣平躺在腹部（通常，只有腹部、胯部，也许还有大腿需要完全平放在表面上），同时从后面插入。