A girl named Mishe is often a girl that has lots of experience(in life). She is also very "fab", shiny and is rearly at home if a party is on in the block. Therefor also used as a term to describe "partygirls". Often used in Japanese, but also in other big Vestern city's, such as London, Berlin and New York.
If a girl(not named Mishe) is referred to Mishe, it is a good thing. To be 'Mishe' is a compliment, in many cultures.
That girl is so Mishe!
I would like to have a piece of that Mishe!