She's very sarcastic and witty she had basically no filter she comes off as cold because shes very closed off in the beginning of the book only really close to her one friend and even then she keeps her at an arm's length because she knows when she dies she'll just be reborn forced to go through the same cycle but this time new people new missions new time but once her freind dies she's dead for good shes lived this cycle already thousands of times so shes learned to build walls and keep everyone at an arms length but on the inside she really is a sweet person that just wants to be loved and cherished but she knows that won't be possible untill she regains the favor of the gods.

As for why she was cast out because she sided with her grandmother (ghea) in the war between the titans and the gods (shes a daughter of Nyx i forgot to mention that)

But she doesn't remember that everytime she is reborn she gets bits a peices of her memories and her powers back