Mia looks and sounds and acts, for the most part, like a girl in her early teens.  She and James are best buds, and they hang together and game together whenever she and her father Henrich get to drop into visit with the Vigil. Which, because of the bad blood between Henrich and Bernie, isn't a lot.   But in Mia's case looks can be extremely deceiving.  She and Henrich were born in 15th century France.  Mia became ill and was dying, and to save her life (because he erroneously believe Bernie would not help) he delved into some  terrible, forbidden necromancy and bound his daughter's soul to that of a primordial. It granted them both immortality, but at a price, for it also inextricably locked them together. She has the ability to turn into a monster-munching monster with a virtually insatiable appetite, but she can only do so if Henrich "releases" her.  So, she is basically an 800 year old kid who wants nothing more than to be with James and game 'til they can't game no more, but she also, when she has to, has no problems morphing into this enormous freakazoid monster that eats everything that opposes her.  With relish.  (sorry.  No I'm not).  Like James she's mighty battle savvy, although a lot of that knowledge comes from practical experience as much as online campaigning. She is absolutely fearless, a bit of a smartass and very, very dangerous. She is the only one other than Henrich and Bernie who know why they don't get on, but she wants no part of the "feud". All she wants to do is be with James as much as possible. And be a kid.