The Rook by Daniel O'Malley - The Literary Phoenix
I don't think that The Rook ever pretends to be a serious work of fantasy fiction. Myfanwy Thomas has had her memory erased. She's doing her absolute best to pretend that HASN'T happened so nobody will noticed. All she knows for sure is that something fishy is going on in the Checquy, and it's why she's in this position. Plus that person is probably still trying to kill her, so Myfanwy 2.0 needs to figure out what's going on, quick.