Wearing a diaper is good, using one is great, but what if a pony could go beyond that? What if a pony could, in fact, be a diaper? Twilight Sparkle never seriously considered the answer to this question until an old friend's obsession proved that with sufficient determination, or sexual frustration, anything is possible.

Contains: the standard from me, diaper wearing, use, and messy diaper sex. Later chapters will contain diaper transformation.