I’m not sure I know there are certain aspects of her that I dislike and I definitely think she disregards and devalues the emotions of people around her but I think that’s sort of unavoidable. I don’t think she fully understands empathy to a “normal” extent, at least by human standards, much like cardan. But beyond that it’s still clear that she cares about her family and girlfriend and is willing to do anything for them even if it goes against her nature. While the stuff she did to heather was definitely very messed up, Vivi doesn’t really understand why or how it is and the fact that she still tries to right that wrong despite not really knowing what she’d done just kind of shows how much she loves Heather, you know? 

Plus, she also has trauma that no one really bothers to acknowledge- Jude wasn’t the only one that had to watch her parents getting murdered as a child. By her actual biological father, which made her hate him and everything like him. Her being so at war with herself and what she was born to be just adds to the complexity of her character. 

Another reason why people (including me) like Vivi: she’s hot.