These are the moth and butterfly cloaks designed and sold by Spanish costume designer Alassie of Etsy shop Costurero Real (previously: unrelated bird wing scarves). The cloaks cost around $225, are made-to-order, and can be printed on a variety of different fabrics. They also have a wire in each wing so you can move them like realistic butterfly wings when you're dancing through the forest pretending you're an earth spirit or tree fairy or whatever the hell people pretend they are when they're dancing through the forest wearing a butterfly wing cloak. Acid makes people do wacky shit.
Keep going for a bunch more shots, the last of which I'm pretty sure is Alice from Alice In Wonderland all grown up.
Thanks again to Ruby, who agrees if you're going to pretend to be something in the forest, go big and be a bear.