Mirror Cadance 2.5 (Patreon)

 Cinch is purely a sexual creature. Twilight's mom is bad, but she actually has control over the magic. Cinch's magic has full control of her. Like she has become an avatar for the magic like Boulder. The only difference is she can move...

Cadence could never know that her actions and hate for Cinch would have ended up like this, but they did, and she is only too happy with the result.

A few things I thought of. It is rare to see Cinch without something in her holes. She normally has a dildo and several anal beads in her ass at all times. Maybe in her mouth as well. Her gag reflexes don't exist. Her magic would have changed every aspect of her anatomy. She can live off cum and pussy juice while her body now secretes a thick, viscous lube for every orifice.