A mystery story 'After school'

Last day in august was my birthday. And I receive a book as present from my cousin. So, Resently, I read that book. That book's title is 'After school'. That is a mystery story. Actually, At the first I don't like that story. I don't like book itself.  And especially I hate a mystery story. Because a mystery story is so scary and made me nervous. So at first, I read that for express appreciation. But as time goes by, I begin to interest that story. I read that more than half. The plot of this story is a murder case in girls' high school. When I read the whole, I'll tell you suspect. I'm so curious next story!