Sonia Nevermind, Ultimate Princess. Sonia is a very cheerful and polite girl who's very curious about Japanese culture. She has this strange dream of becoming a normal highschool girl. She often says things out of place due to her lack of normal vocabulary since she's usually very formal as she is in fact a princess. Although she seems like a pure girl at heart, she does have an odd obsession with serial killers.

Voice reference: https://www.youtube.com/watch?v=h03gOWGcgQs 

(It doesn't need to be an exact copy of the voice!)