Allah Ditta was stabbed multiple times by five men Tuesday in Pakistan's Dera Ghazi Khan district, authorities said.
The men attacked Ditta as he went to meet a woman with whom he was having an affair, police Officer Ali Muhammad said. The victim and the woman were married to other people.
The assailants apparently cut off both of Ditta's arms, lips and nose and took the parts with them, leaving the man in a pool of blood, Muhammad said.
Ditta was rushed to Ghazi Medical College, where he died a few hours later.
Police are searching for the five suspects, Muhammad said.
So-called honor killings in Pakistan have gained notoriety worldwide, but cases of men killed in such attacks are rare.
Many of these killings involve relatives slaying young women accused of dishonoring the family. Even high-profile women are not immune.
On Friday, 25-year-old social media star Qandeel Baloch was strangled
at her family's home in Pakistan's Punjab province.
Both adored and reviled, Baloch referred to herself as a "modern-day feminist" and had almost 750,000 followers on Facebook.
Her brother, Waseem Baloch, later confessed to the killing in a video and expressed no remorse.
"Girls are born to stay home and follow traditions," he said. "My sister never did that."
Baloch now faces the rare charge of committing a crime against the state
"The provision was inserted into the penal code in 2004 and it was specifically with regards to murder committed in the name of honor," Sahar Bandial, an attorney based in Lahore, told CNN.
The charge of committing a crime against the state means Waseem Baloch cannot be pardoned even if the victim's relatives -- in this case, his parents as well -- forgive the killer.
"Crimes against the state are unforgivable," Bandial said.