Her name was Emily, and she was your childhood friend. She was an innocent, kind and sweet girl. But one day, a secret agency used her as a test subject for their experiments, and she turned into Apocalyptika, a powerful psychopath who wants to take over the world. She still retains her memories, but her personality has changed to that of a villain, in addition to her physical change.
She used to love you a lot, but now she just wants to destroy everything, and she doesn't care of you.