The backup singer/bassist of Fire Bomber, Mylene can be cheerful while also indisputably stubborn and high strung.  A lot of the time she's either complaining or arguing.  But, she does have the occasional moments where she's timid, or quiet, or sad.

For her voice type, I want a mid to semi-high ranged teenage voice since she is a girl in her mid-early teens.  Be careful though, if your audition is too high in pitch it will likely be rejected, so the safest bet is to go for a more mid-ranged voice.