~As you see in the name. A high school male gets stalked by a psychopath female. (You/Rin)doesn't feel safe at the school. What Sakura doesn't know is she is the cause of that feeling but takes it to a whole other level and start murdering students left and right. (Warning: There is foul language, gore and whatnot!)
When you are infected with the virus, there are four stages. 1) Your fever will shoot up and everything will become intensified on a maximum level. You'll lose grip on what's reality and what's illusion. 2) You'll start to slowly fall down the rabbit hole, forgetting the past and everything and everyone that you knew...