Additional Info.
JaneJane is a sadistic guard of the Volturi and a pet of Aro's. She seems rather bitter and easily justifies inflicting pain on anyone with her power. Jane has a twin brother named Alec and they both reside in Volterra, Italy.
The Volturi had their eyes on Jane and Alec as potential people to change back when they were still human, but were waiting until they were older to change them. When frightened humans tried to burn the twins at the stake, because of suspected witchcraft, Aro stepped in. Because of all she went through, she gained her power of being able to voluntarily inflict an illusion of antagonising pain. Aro was forced to change them while they were still young and kill every human who tried to burn the twins. Jane has since become one of the prize members of the Volturi Guard and is one of their highest ranking members.