Yuno Gasai

"The Queen Of Yandere" Yuno Gasai (我妻 由乃, Gasai Yuno) is the female protagonist of Future Diary series. She is the Second Diary Holder and possesses the "Yukiteru Diary". Yuno's personality is an ambiguous one, for the most part she is a sweet, feminine and sometimes shy girl when around Yukiteru Amano. This masked her darker side that is of a ruthless, cold and calculating sociopath who has little if any problem in using others for her ends, that is her and Yukiteru's survival. She will resort to cruel and mostly violent methods that most of the time end in bloody deaths, of either the Diary Holder or any follower, effectively making her a Yandere. However, she was not always insane. Her brutal personality is a result of circumstances surrounding her life, mostly the abuse she endured by her mother and the absence of her father, which finally ended with their deaths two years prior to the Survival Game. This was the beginning of her changes, as she later became quite lonely and sorrowful. So from the point onwards of when Yukiteru told her they would marry when they grew up, it was the pillar of support she needed, and her obsession for Yuki grew to escalating proportions. Willing to harm those whom she believes will take Yukiteru away from her, such as friends, etc.