Very nice. Art and music are great for one. At first I thought the splitting and touching mechanic were roundabout ways to do the "switch-between-characters" mechanic, but it did make more sense given how each section was meant to be played by a separate piece rather than switch between all of them. Though I might recommend you polish that mechanic if you ever decide to expand this game.
Now that said the very nature of them having to be done piece-by-piece does make it feel like wasted potential for the idea of being able to carry and throw other pieces, but that's not a serious detriment. Something I did notice though is during the end scene it can be interrupted if the player tries to move, so you may want to disable player control entirely during that last scene.
Overall a solid piece.
I'd like to wish all fellow game designers and artists good luck in the Construct 3 Game Jam!