Don Belton, an assistant professor of English at Indiana University and one of the leading African-American voices in academia, was found stabbed to death in his home on Monday, the Associated Press reports.

The police held Michael J. Griffin, 25, after he admitted to the stabbing. Griffin reportedly stabbed Belton, 53, because the professor sexually assaulted him on Christmas Day and showed no remorse. Griffin, a former Marine, said he went to Belton’s home on Sunday to confront him about the assault and that an argument and scuffle ensued.

According to his affidavit, he stabbed Belton with a 10-inch military style knife after Belton failed to “show or express any type of feeling that what had taken place was a mistake.”

An initial hearing for Griffin was held on Wednesda, in which he pleaded not guilty to Belton’s murder.

Belton had contributed pieces to Newsweek and The Advocate, was the author of the novel Almost Midnight, and was the editor the anthology Speak My Name, an exploration of the realities of black masculinity.

“Belton was a literary path blazer and one of the important black gay writers to emerge in the 1980s,” Northwestern University professor John Keene told Rod McCullom at Rod 2.0. “His 1996 novel, Almost Midnight, heralded a wave of works to come. Kind, friendly, and very smart all come to mind when I think of Don.”