Police said the boy, who has been arrested, also allegedly used to sexually harass her by sending SMSs on mobile.
The girl, doing her second year in an Arts and Science college at Gobichettipalayam near here, allegedly set herself ablaze on Saturday last. She succumbed to burns in hospital today, police said.
The boy reportedly used to frequently profess his love for her, sources said, adding, a case has been registered.