The male student at Columbia University who Emma Sulkowicz named as her rapist is now suing the Ivy League school, its president and one professor for defamation.

According to the New York Times, Paul Nungesser accused Columbia, University President Lee Bollinger, and Jon Kessler of allowing Sulkowicz to smear his reputation. For her visual arts thesis, Sulkowicz vowed to carry the mattress she said she was raped on around campus until her rapist is punished.

Sulkowicz's project, "Mattress Performance (Carry That Weight)," has gained national attention, especially for taking place at a school under federal investigation for alleged Title IX violations. Nungesser accuses Columbia for contributing to harassment he has experienced by allowing Sulkowicz's project.

"By refusing to protect Paul Nungesser," his lawsuit reads, "Columbia University first became a silent bystander and then turned into an active supporter of a fellow student's harassment campaign by institutionalizing it and heralding it."

Columbia found Nungesser not responsible of rape in Sulkowicz's complaint, the Times reported, sparking her demonstration as she felt she did not get justice. Her demonstration also comes amid a national discourse on campus sexual assault, which includes two White House campaigns to curb what the President called "an epidemic."

"I think it's ridiculous that Paul would sue not only the school but one of my past professors for allowing me to make an art piece," Sulkowicz told the Times.

Nungesser is a German citizen, the Associated Press noted, and said Sulkowicz was his friend at one point before she started calling him a "serial rapist" repeatedly.

"It's ridiculous that he would read it as a 'bullying strategy,' especially given his continued public attempts to smear my reputation, when really it's just an artistic expression of the personal trauma I've experienced at Columbia," Sulkowicz said. "If artists are not allowed to make art that reflect on our experiences, then how are we to heal?"

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