Manga by author Saitou Misaki - Status ongoing

From FairGame:Narukami Tasuku isn't just an average high schooler. He can see ghosts and demons, even though he doesn't want to. One day he was involved in an incident and found out that his family are the totsugamimori, the ones who protect the totsugamizuka. Also he is the only person in his family that can become the heir of the totsugamimori, and now, as the heir of tosugamimori, he is being dragged into their world...

At the old and abandoned school campus, some students committed suicide in the past, leaving behind a blood curse. A student, dubbed 'Shinigami/ The God of Death' by other students, went exploring the old campus with his friends. Halfway, someone dropped their flashlight and a dismembered woman's body is discovered.