So it's revealed anna transformed herself into Zoey so she could break her and her brother up.

so here's how she died and why she's angry with these two.
anna was big into having her brother's attention and he would always give it to her until he met Zoey he almost ignored his sister until one day anna got an idea she was gonna take some pills and call her brother to come to save her, so stupidly she took a bunch of some random pills first but his phone was off and poor anna died alone in her room.
as you know she became a demon and tricked her brother into killing his girlfriend (which is still no excuse) then while he was running away he happened onto a set of train tracks which as anna mentioned she pushed him onto and convinced him to relieve killing Zoey by dimension hoping.

last: https://www.furaffinity.net/view/48100838/

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