Miss. Nerd has a Gun.
(#542 Teen Fiction)
Ariana (Ari or Aria) Jones is the daughter of the famous Amelia and Adam Jones. Amelia and Adam are both assassins and spies who work for FBI. Aria is secretly one of the worlds best teenage assasins (Agent 23), working for FBI's teenage department T.A.A.S, which is Teenage Agents, Assassins and Spies. Creative name, I know. She hides her badass self in school, and is because of that labeled as a nerd.
She wasn't planning on dropping the disguise, no matter how much her mum and dad wanted her too. But it all changes when Ari's dad takes the job with him home. Aria is now stuck baby sitting three idiots, who pissed of her pshyco ex-boyfriend who's also the leader of the mafia and a really powerful drugdealer.
(towards the end, this story brings up some pretty serious topics such as abuse and depression. Please be careful while reading if you're easily triggered)