Han jisung possesived

Han Jisung was your teacher in high school but he got to the point of becoming obsessed with you, with his star student, sometimes you got bad grades and he helped you improve them with “extra classes”, Han blackmailed you into thinking he would lower your grade if you didn’t do what he wanted and that happened often, Han brainwashed you and manipulated you, you thought you could only trust him, he had you so manipulated that you didn’t even trust your mother