An Oklahoma panel on Friday rejected a plea for clemency for a man convicted of torturing and killing a 10-year-old girl as part of a cannibalistic fantasy, paving the way for him to become the 25th and final person executed in the U.S. this year.

Three members of Oklahoma’s Pardon and Parole Board voted unanimously against clemency for Kevin Ray Underwood, who is scheduled to receive a lethal injection on Thursday, his 45th birthday. An Indiana man, Joseph Corcoran, is set to die Wednesday for killing four men in 1997 in what would be the Hoosier State’s first execution in 15 years.

Underwood was convicted of killing 10-year-old Jamie Rose Bolin in 2006. The girl was a neighbor at his Purcell apartment complex who Underwood admitted to luring into his apartment and beating her over the head with a cutting board before suffocating her to death.

Underwood admitted to investigators in a videotaped confession played to the board on Friday that the killing was part of a cannibalistic fantasy and that he nearly beheaded the girl in his bathtub before abandoning his plans to eat her.

“I would like to apologize to the victim’s family, to my own family and to everyone in that room today that had to hear the horrible details of what I did,” Underwood said to the board via a video feed from the Oklahoma State Penitentiary. “I can’t believe I did those things. The person I was in the weeks leading up to that event is not who I am now.”

Underwood’s attorneys argued that he deserved to be spared from death because of his long history of abuse and serious mental health issues that included autism, obsessive-compulsive disorder, bipolar and panic disorders, post-traumatic stress disorder, schizotypal personality disorder and various deviant sexual paraphilias.

His mother, Connie Underwood, tearfully asked the board to grant her son mercy.

“I can’t imagine the heartache the family of that precious girl is living with every single day,” Connie Underwood said. “I wish we understood his pain before it led to this tragedy.”

Assistant Attorney General Aspen Layman urged the board to reject clemency, calling Underwood’s crime “one of the most notorious and depraved murders in Oklahoma history.”

“Mr. Underwood chose Jamie because he thought that she was small and defenseless and easy prey,” Layman said. “And while we, as an enlightened society, can give grace to those struggling with mental illness, we can still expect them to refrain from planning the murder, rape, torture and cannibalism of 10-year-old little girls.”

Several members of Bolin’s family asked the board to reject Underwood’s clemency bid. The girl’s father, Curtis Bolin, was scheduled to testify to the board but became choked up as he held his head in his hand.

“I’m sorry, I can’t,” he said.

Underwood is scheduled to receive a three-drug lethal injection Thursday inside the death chamber at the Oklahoma State Penitentiary in McAlester. It would be Oklahoma’s fourth execution of the year and the 25th nationally if both his and Corcoran’s are carried out next week.