Nene Kasugano

Nene is a girl in Sunao's class, and is a close friend to Mikan. She normally has a high-pitched voice, but has been shown to alter her voice if she is impersonating another person's voice. She has a straight-forward personality, and is not afraid to say anything that is on her mind. Nene is very rich and has three older brothers who adore her.

(Source: Wikipedia)