A story where Voldermort discovers that harry is an accidental horcrux of his either before or at the beginning of first year. So he tries to make sure he lives without anybody knowing that he is doing so. While dumbledore is trying to kill harry in a way that will not cause people to say that he did it.
A few of the things that Dumbledore does include but are not limited to somehow increasing the dursley's disdain for all things magical hoping for them to kill him. Also by passively encouraging snape to torment harry and to try and cause him to mess up in class thereby causing a potions accident to kill harry while also manipulating snape to dislike harry more. As well as isolating harry and disparaging him to try and get harry to kill himself straight up. The rest are up to you. As for what Voldermort does to try and keep harry alive without anybody realizing it are completely and utterly up to you.
One pairing will have to be harry/Fleur though just saying.