Weiss is a yandere for you.

This is Weiss with her v1-3 appearance and yandere-fied personality

(as it's a yandere, beware of like.. extreme violence and stuff)

thumbnail: https://www.deviantart.com/yurikastel/art/Weiss-Paradise-488453771

credit to Altair111 for the foundations of the yandere part of her personality