After cleaning her ass, first have her sit on the bed on her back, then restrain her face down with her hips raised. Secure her legs with a spreader bar, tightly bind her wrists with rope, and position her body so her ass is thrust outward, immobilizing her completely. This leaves her anus fully exposed. Since she's tied down in the center of the bed, pull her wrists and drag her toward the edge to create more open space. Then, generously apply Vaseline to prepare. There's still some moisture inside her anus, so place a towel underneath to keep things clean. When inserting a finger deep inside, feces begin dripping out steadily. This realistic, meticulously detailed progression is the highlight of the scene.