Zashisu 

One day, middle school teacher, Kai Yamauchi, hears of a murder on the news. The victim, Yuuki Suzuki, was his classmate back in middle school. A few days later, Tamao Yagisawa, Kai's girlfriend and a newbie book editor, discovers a story with a death scene ressembling that of the murder; "Zashisu," written by Haruto Saeki. Then, just like in the story, Kai's old friend receives an invitation to a class reunion... This is the first volume of Masamori Morita's first attempt at a suspense horror story!!