"Lost in the Shadows Part One"

(Credit to Shannon Messenger because I took some of the story aspects from her series 'Keeper of the Lost Cities')

Eleven-year-old Clara Halfmoon is failing.
Every Mentee in her Echelon at a Bluebell Academy - the magic school for vampires that she goes to - has obtained a Talent, except for her.
In the midst of attempting to prove herself to her Mentors and get her grades up, she learns some terrifying information: she is being watched.
Being watched by Poison, the mysterious group of killers that recruits Mentees from every magic school in the huge kingdom of Elementdom (in which Clara lives) who they think are Worthy.
If Poison finds a Mentee who is Worthy, they Possess them into recruiting other Worthy Elementdom Mentees.
They were waiting for Clara to obtain a Talent.
The really awful part of this routine is that no one - Mentee, Mentor, or other - knows why Poison are kidnapping Mentees.
Once the Mentees have brought back another Mentee, they are never seen again.
Which is the exact reason why Clara is scared for her life.
But the terror isn't over quite yet.
Clara accidentally commits a crime and is handed over against her will to Poison alongside her best friend, Sigrid Peters, by the cruel Elementdom royalty.
Clara has lost all of her friendships, besides Sigrid.
She's being pulled into Poison's brutal trap...
But everyone knows that Clara Halfmoon doesn't give up so easily.
Death seems to be dangling right in front of her face, and Sigrid may be lost forever, but there is a small spark of hope...and Clara can feel it.
Elementdom may be ruined forever if she chooses to ignore the spark...so Clara has to think fast.