Danny Phantom x Yandere Simulator crossover
Yandere-Chan's family moves to Amity Park after her School got burned down killing her senpai in the prosses, Feeling like she will never find anyone like her senpai, Ayano accidently bumps into Danny Fenton an average high school student with ghost powers he keeps secret. Ayano soon finds out his secret and it just make her to fall in love with him even more, but when other people starts to admit their feelings to Danny and his other self. Well, they just need to be remove from the picture... for good.
This is before Phantom Planet.
Anyone want's to create their own Danny Phantom and Yandere Simulator crossover story, be my guess.