Marionette
Marionette
So I understand that technically speaking the "Marionette" or the "Puppet" doesn't actually have a name, but I am partial to "Marionette" so let's call it that shall we?
So first we come to the question of what the Marionette actually is. In the "Give Cake" minigame you face after you die, you can look out above the room and see a crying child that is shortly killed by a purple man (more on him later) and turns grey. The child has the same tear marks as the Marionette, leading many to believe that the child became the Marionette. This always bugged me for some reason, and I finally realized why. The kid was crying outside the restaurant seemingly because he wasn't able to go inside and get cake, so he was lonely. Why would the child's soul, which before haunting the Marionette was haunting the entire restaurant, choose to take control over the Marionette, the most alone character in the franchise. It sits in a box until somebody wins a prize. Why? If the kid wanted to be a part of the fun, why not posses Freddy, Bonnie, or Chica, the most recognized and important and beloved animatronics? Maybe the child didn't know. Maybe the kid's soul thought that the others were alive, and chose the Marionette because it appeared limp and lifeless and alone, just like they were.
Now, what is up with the music box? How and why does it calm the Marionette? This is one that I am not really sure of. Maybe it just reminds the soul of the kid of his peaceful days of life, or it might make him think that it isn't time to be out, since after all, it is sitting inside a giant jack-in-the-box, maybe it thinks that as long as the music is playing, it can't pop out.
Now I know this was short, but I don't really care much for Marionette mysteries.