[Tip]

I don't think it's because there is anything wrong with her.

She only does it in certain circumstances and I think it's because she thinks the camera might be on her. She is not a good actor in terms of body language so it comes out all a bit odd. Like her excessive hand signals in the diary room.

I think she gurns to express emotion in situations either where she is forcing it or not able to express naturally. There's quite a lot that is socially awkward about her, but I don't think that's anything wrong.