CAMBRIDGE, Mass. — In a brightly lit classroom here at Harvard, Mia Karvonides was trying to explain to a group of bemused student leaders the difference between a romantic encounter and “unwelcome conduct of a sexual nature,” as the university’s relatively new code of sexual misconduct defines it.

She tried to leaven the legalistic atmosphere at the town-hall-style meeting with realistic-sounding examples, defying gender stereotypes. Jose and Lisa, chemistry students, are working late at night in the lab, she began, when Lisa comes up from behind and kisses Jose on the neck.

Such a surprise move, she suggested, could be the beginning of a sexual misconduct complaint. “I want to acknowledge that this isn’t so simple,” Ms. Karvonides said. “I don’t have any magic words for you. It takes a little bit of a closer look to grasp the concepts.”

Ms. Karvonides is Harvard’s first Title IX officer, leading a new bureaucracy that oversees how the institution responds to complaints of sexual violence under Title IX, the federal law that governs gender equity in education. She is one of a rapidly growing number of Title IX employees on campuses nationwide, as colleges spend millions to hire lawyers, investigators, case workers, survivor advocates, peer counselors, workshop leaders and other officials to deal with increasing numbers of these complaints.