I am Silver. 

Yuno's personality is an ambiguous one. For the most part she is a sweet, feminine and sometimes shy girl when around Yukiteru. But, this masks her dark and sanguinary side--a ruthless, cold and calculating psychopath who has little, if any problem in using others for her ends- her and Yukiteru's survival. She will resort to cruel and usually violent methods, most of the time coming out of nowhere, that generally end in bloody deaths, of either the Diary Holder or any respective follower, effectively making her a Yandere.