Just who is this 'Law Professor'? She appears to be a senior investigator who can order the police around, follow up on random people and their backgrounds, install CCTVs at odd places and pass cryptic messages in fortune cookies. She's stalking Sanju every time they're in the same scene- calling out to her in class all the time with peculiar examples, asking about her missing friend, even stating before class that 'a secret came out' when Varun disappeared. I'm quite sure she set up the fortune cookie incident. I'm quite sure she also set up the CCTV in the change room, and also locked Sanju inside.
Her connection to that tattooed, hood-wearing character is unknown, but her connection to Prithvi is clearer. Prithvi resembles the policeman who taunted the BFFs about Varun, supplied the fortune cookie batch with the mysterious fortune cookie, and seems to know a lot more about the BFFs than any other new student. Her connection to Sanju, though, is a lot deeper than we've thought. Her connection to Varun, now, that should get us thinking- maybe she's got a reason for so much interest in Varun's case?