I really like the design of Morrigan and the way you've drawn her. You've got a great art style that I enjoy and it makes a character look like a genuine Sonic character right out of the series. I in particular love her face, the shape of the beak being my favorite and a more unique shape from the canon avians we've seen (Babylon Rogues). It's honestly where I find myself looking at most. Her clothing colors are a nice contrast to the dark colors of her feathers and it really makes her stand out more. Her stance even works with that manipulative and independent personality and you've captured her character well in the stance.
However, there are just a few technical issues that come out to me. I'm not sure if it's just me or the boots playing tricks on my eyes, but it almost looks as if her knees are bending the wrong way a bit. The wings almost look like they're barely clinging to her shoulder blades. This may just have been the way you drew them, but they don't look like they'd open that much even. I'm not sure if height was your intention, but she seems too tall, even by tall Sonic character standards.
While I enjoy her personality and how well you've managed to capture that, I can't say that I enjoy her backstory. Some part of me just doesn't really buy the idea that an avian would be bullied for a genetic mutation in which her wings were on her back. Birds have wings, it doesn't seem that big of a deal if they're on the arms or back. I'm not saying that you can't have wings on the back, because that's totally ok. Rouge has wings on her back and bats wings are their forearms just like birds. I just don't find myself buying what you're selling in terms of her backstory. To me, it doesn't seem that big of a bully-worthy deal for a bird to have their wings on their back. The stalker part I'm ok with since shit like stalking and attempted rape does happen and it's a more gritty and realistic aspect of life, something that the Sonic world doesn't often touch upon. I even find myself intrigued by who this person who saved her is and whether this had something to do with her current state and personality.
Overall, the art style is great and really polished, and the colors go together rather nicely. The genetic error is really the only thing in the backstory I have a problem with just in that I don't find it that believable. The character is something more unique in the world of Sonic characters, however, I'm not really that blown away by her.