Life Double Lived

Casey is a normal teenager.... Well for the most part casey has split persionality disorder (SPD) and while casey herself is very nice, quiet, timid and caring, lucy,her alternate persionality isnt she is loud, sarcastic and bold.
Unlike most cases of SPD where the persion has no idea they have an alternet personality both girsl are aware of it and are actually really good friends cause if you have to share a body might as well get along right? Lucy really only comes out on weekends or when casey needs help wile casey is out all the time and the only friend she has is litterally inside her head.
Chase is the leader\alpha of the biggest gang\pack in the world he is 18 and is looking for his mate what happens when he finds her? Well them cause its really a two-in-one package deal.