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Having seen those I loved die a vision of my destruction would be welcomed. However it turned out that I was not to die, well not immediately. I was asked to join the guard after being assured I wouldn't be pardoned like Alice had been.
My fate was sealed if I decided to join them, become a member of their guard I would be used to read people's minds, reporting back my findings. That way Aro would always know the truth, his enemies would have nowhere to hide. His gift although similar to mine, worked through touch. Those of our kind that knew of The Volturi knew this, so anyone wanting to hide their thoughts would simply refused physical contact I had no such limitations. His anger when I refused him was palpable. The scream that rang through the castle, the one thing Aro hated, was being denied.