The girl, studying in first-year, had lodged an FIR on September 18 with the Siliguri police, claiming that her senior Aninda Garai took her to a private boarding, where he stayed, for helping her with some drawings.
According to the FIR, she was given a soft drink laced with drugs by Aninda, who later shot an obscene video of the girl.
He, later started forcing her to marry him, saying he would make the clip public if she refused.
When she refused, Aninda circulated the five-minute MMS among other students, she said in the FIR.
"The police failed to provide any relief even after a month," the girl's father Nilu Saha alleged after she committed suicide on Wednesday.
Darjeeling Superintendent of Police D P Singh told reporters that Aninda was absconding and a police team had been sent to his village at Maheshpur under Sonamukhi police station in Bankura district.
Meanwhile, the SFI, DYFI, Chhatra Parishad and Trinamool Chhatra Parishad have submitted a memorandum to Additional Superintendent of Police Gaurav Sharma demanding Aninda's arrest and seizure of the video.