I love the hidden imagery in this glammed up overalls look, if you can call it that. It's like overalls, meets skirt, meets dress? Someone with more fashion knowledge than me knows the right term and is punching their keyboard right now. You could take that as a W on her chest, which could stand for something like "woman," or "winner," but if we continue the Stranger Things upside down motif, that's an M. Very clever outfit, Millie.
Stranger Things Fact Number Twenty Two: Millie Bobby Brown wasn't so keen on shaving her head (who could blame her), so the Duffers showed her footage of Charlize Theron from 'Mad Max: Fury Road' and that was enough to convince her. Always use the Oscar-winning film when trying to convince someone about your project. No one ever got convinced of anything using the movie 'Freddy Got Fingered.'