Ok, I looked at the other recent picture of Twilight you posted and now I see what's going on here. Without being able to see the full borders of the giant floof of hair you give her, it just looks like an arbitrary patch of the picture got turned hair-colored, covering her ear (the kind of thing an AI would do, which is why I said that). The fact that the shape matches up with the shape of her ear isn't helping here.
Edit: it's an artifact of the drawing convention you use, where the giant hair floof looks good but doesn't really make sense if you translate it into 3-dimensional space, like Mickey Mouse's ears. In this picture it conflicts with the ear a bit, to my mind.
I want to add that I just got my meds after being without for several weeks, I haven't slept in two days, and my filters are suffering. I apologize sincerely if I've been offensive.