Sometimes you are invited to a masquerade ball, but cannot find a matching mask for your garment. Why not consider designing a special one for yourself? No one else would wear the same mask as yours, and it's custom according to your face, just like Cinderella's Glass Slipper. The mask, covering only half of her face, smartly uses the butterfly to hook her ear so that no elastic band is needed. For making a small-batch of production, 3D printing is the most economical method.
https://www.facfox3d.com/3d-printing-service/sla-3d-printing-service/sla-3d-printed-custom-butterfly-mask.html