Read manga: Ryouko No Shinrei Jikenbo

manga
Summary:

Ryouko Midorikawa is a girl in her first year of high school. One day the cat she had raised and loved for 15 years suddenly dies. Although Pow hated water, he died drowning. Ryouko is lost in questions about the cause of his death. But from that night on, terrible things start happening everywhere around her!