The reflection in the mirror acts as it should. It does not blink out of place, or fall behind, or turn the wrong way. It perfectly copies her movements, as it should, but there is no glass there in the mirror. It's empty. Or it's open, rather, open and allowing. The pony behind it is just as tangible as her. The hoof reaches outward. Feels its own, its kin.
The hoof touches hoof, not mirror.
When she reaches into the mirror, she touches herself. Twilight is not afraid or upset. She's not even shocked. There is contentment, expectation. This is the way it always should have been, her hoof touching her hoof. She intwining her own flesh. The hoof itself is strong and hard. The flesh behind it is spongy and soft, she feels, applying and decreasing pressure - pushing into and out of the hoof. The other face looks towards hers. The smile is slight but definite. There is a twinkle of life in her eye, something so true and real that never catches in the eyes of the dead and the dying. It's her card, her proof. The hoof touching the hoof. The face yearning for a closer look, the maw dipping inwards. The eyes twinkling and resting.
A press of lips, a slip of tongue.
A single moment, she is tangible.