SALT - Lucy/Nyu from Elfen Lied

 

Elfen Lied is a rather bloody anime and manga about Lucy a "diclonius" meaning she has invisible arms called vectors, who's hatred for mankind leads her to seek vengence. Whilst escaping from the lab where she was held captive she is injured a split personality - the childlike and innocent Nyu is born.

SALT portrays both Nyu's sweetness and Lucy's cold stare. The diclonius horns are my favourite as they avoid looking like dodgey cat ears. It's a really cute cosplay.
You can check out her cosplays here the L is possibly the best I've ever seen.