It is clear why a black figure appeared in your drawing of Barbie in the Barbie world - the movie mentions death.
That's why the movie is not for under 13s. This movie with Barbies, they made it for us older people, and here it is in our consciousness, the mentioned topic appears when we least expect it.
Hahahaha didn't know that the movie is so extreme to mentioning death. 😃Death in general has the nasty habit of appearing uninvited.