If she has a sight disability, why would she wear glasses without corrective lenses?
On most of illustrations, this red-haired "myopic big sister" is always portrayed as always needing her glasses. It seems that she has been nearsighted since school years, based on the artist's previous works. Anyways, based on this image, is she going to put her own glasses on the viewer for some flirty reasons?
If now you can assume that she's wearing glasses without corrective lenses, I assume that she might've put clear fake glasses over her eyes that wear prescriptopm contacts. Some find that the lens thickness on the edges of myopic glasses look unattractive and nerdy, but I found them appealing on girls.
