in like the second or third chapter the doctor is talking to his friends about how he dumped someone, “the hottest guy in the club”? yeah i think the stalker is him, or else why would that little segment even be included. idk but that just makes the most sense to me. plus when the doctor’s other ex that he recently broke up with ran into the hoodied stalker he was saying stuff like “how could he have dumped someone to make him this angry” or something like that. so i def think it’s someone the dr dumped. anyways that’s my theory and if it’s not him im gonna look really dumb but oh well lmao