Curse killing arc - Ryukishi07

Satoko's uncle has returned and is abusing Satoko, but her history is so complicated that a simple call to child services isn't going to help. So Keiichi decides to take matters into his own hands and just eliminate her uncle. He does it on the night of the Cotton Drifting festival, hoping things will return to the peaceful fun days they were before. But when he talks to everyone at school, they claim they hung out with him all night at the festival and that Satoko's uncle isn't dead. As more and more people begin to doubt Keiichi's sanity, he grows angry and wishes they were all dead. But when the victims of his silent rage actually begin dying, the mystery in Hinamizawa begins to unfold.