Briefly about Dorei Yuugi (Kimura Takashi) manga:Kai is just your average high school student until one day he receives an email inviting him to try a mysterious new cellphone game. The people whose pictures he takes with the application, and with whom he exchanges contact info, go missing one after another... A vicious and cruel game commences! Now called upon by a group calling themselves--The Slave Hunters--Kai must find and rescue his captured classmates. But what is this game? What are its rules? And why do the hunters want him to find the missing students so badly?…'''