A California man who killed and dismembered his live-in boyfriend, leaving some of the remains at a cave used used as the "Bat Cave" in the 1960s "Batman" series, has been sentenced to 25 years to life in prison.

Gabriel Campos-Martinez, 40, was sentenced on Monday by Los Angeles Superior Court Judge Katherine Mader, who urged him to explain why he killed 66-year-old Harvey Medellin, according to the Eagle Rock Patch.

"We never really learned why," Mader said. "It has always been a question in my mind." 

Campos-Martinez earlier declined to make a statement after listening to the victim's niece and three fiends talk about him, reported the Associated Press.

"We miss his voice, we miss his laughter and, most of all, we miss his presence," Medellin's niece Christina Medellin Serrano said, noting Monday would have been her uncle's 70th birthday.

"The horrible demise of my friend, Hervey Medellin, has made this world a darker, colder place," said Amelia De Vivar.

The judge told Campos-Martinez that the crime had a darker meaning for those involved because it was "so inexplicable, so evil, so depraved," especially given that the victim "was providing everything for you."

Records indicate that Campos-Martinez had lived with Harvey Medellin in a Hollywood apartment after meeting while hiking in March 2011, before strangling the retired airline ticketing agent in December of 2011.

Medellin's head and other body parts were scattered near a hiking trail in Griffith Park near the iconic Hollywood sign, reported News 24. A dog with some hikers found the head on Jan. 17, 2012, while his hands and feet were found a day later.

Campos-Martinez was arrested last year in Texas.