Fuck, all this plot came out of nowhere like Truck-kun and hit just as hard. ;_;
So this explains that her eyepatch isn't a fashion statement and she's truly half-blind.
Also explains why Evan-san would conveniently have a Christmas dinner spread and plush bear at his home on the night they first met. Rereading Ch.1 though Evan-san said that if she was a good girl for a whole year they have Christmas together again, and looks like he kept his word so that's nice.