After fiddling with poses and expressions, this was born. There is a little secret for a friend of mine, but it may be removed once he finds it. Or maybe not, who knows? It's not exactly masterfully hidden, but comparing this video to another makes it easy to spot where it is.

Song: Flourish, Wither, Bye - A Himitsu
https://www.youtube.com/watch?v=_2-BCUCTfhc

Image:
https://www.deviantart.com/kids-in-the-corner/art/Oops-767657912
https://derpibooru.org/1852662