Re-edited from an ollder, but never released, DVD.
LAdy AlexX enters with her dog-slave the dungeon and orders him to lye on a bench.
She mounts her slave's face like a horse, but soon she decides, that he can move to much and binds him with a rope at the bench.
Now helpless, she mounts his face again, sits reverse and begins to play with some toys,like nipple-clamps and brushes.
Part 1 with the first 8 minutes of a one-hour session in the domina-cave-cellar.