Certainly an expressive piece. The composition of the canvas, with her being surrounded by "air" on all sides except down, makes her appear small, rather fittingly. Beautiful shiny mane and tail. And the way the tail lies, low and rather far away, as well as the way the mane hangs down, only add to the expressiveness. Same goes for the lowered ear. Twi's ears seem to strengthen her expressions more than they do any other Mane girl's.
Don't feel guilty, Twily. Don't cry. I can't bear seeing you like this. Let me wipe those tears, love. And I'm not letting go of you just yet, no. I'll be with you always, no matter what.