In an online diary entry from January, Kevin Ray Underwood said he was embarrassed about how many gifts his mother bought him at Christmas and how his father was proud of him for helping him assemble a computer desk for his sister.

"Just Christmas Eve alone made this one of the best Christmases ever to me, and to my sister it WAS the best Christmas ever, she kept saying so," wrote Underwood, who used the screen name "SubSpecies 23."

But scattered among the entries about computer games, family get-togethers and small-town angst are indications of a darker side to the 26-year-old grocery store stocker from Purcell, including feelings of depression and isolation, and homicidal thoughts.

Authorities believe Underwood acted on those feelings last week and lured 10-year-old neighbor Jamie Rose Bolin into his apartment, beat her over the head with a wooden cutting board and suffocated her with his hands and duct tape.

McClain County District Attorney Tim Kuykendall said formal charges of first-degree murder would be filed Monday in Purcell, a small town about 40 miles south of Oklahoma City.

Purcell Police Chief David Tompkins said investigators believe Underwood sexually assaulted the little girl after he killed her and planned to eat the corpse.

According to a police affidavit, Underwood confessed to killing Jamie. Meat tenderizer and barbecue skewers found in his apartment were intended for the little girl, Kuykendall said.

People who knew Underwood described him Sunday as a quiet, "boring" and seemingly trustworthy young man. His mother, who also lives in Purcell, called him a "wonderful boy."

"This is something that I don't know where it came from," Connie Underwood said through tears in a brief telephone interview Sunday. "He was always a wonderful boy.

"I would like to be able to tell her family how sorry we are. I just feel so terrible."

On his blog, an online diary that he had kept since September 2002, Underwood described himself as "single, bored, and lonely, but other than that, pretty happy."

He mentions cannibalism, asking "If you were a cannibal, what would you wear to dinner?" and responding: "The skin of last night's main course."

In an entry dated Feb. 4, 2006, Underwood wrote that he struggled with depression and social interaction.

"Pretty much the only time I believe in God is when I blame him for something," he said. "Or, when I'm really depressed, to cry and beg him to make me better, to make whatever is wrong in my brain go away, so that I can live like a normal person.

"That's all I want in life, is to be able to live like a normal person."

In September 2004, he wrote that his depression deepened after several months without taking the medication Lexapro, an antidepressant also used in the treatment of anxiety disorders.

"For example, my fantasies are just getting weirder and weirder. Dangerously weird," he wrote. "If people knew the kinds of things I think about anymore, I'd probably be locked away. No probably about it, I know I would be."

Underwood worked for nearly seven years at a Carl's Jr. restaurant, where shift leader Bill Verdan described him as a quiet person who kept to himself. "He did a good job," Verdan said.

However, he said Underwood, who quit about a year ago and was working as a stocker at a Griders Discount Foods grocery store in Oklahoma City, was a "boring" man who rarely smiled.

"Just his tone of voice, he just sounded dull," Verdan said. "Trying to get a smile out of him took an act of Congress."

Verdan said he and his wife and young daughters never suspected anything unusual.

"He gave my wife rides home from work numerous times," Verdan said. "We never felt uncomfortable. I talked to my girls after this happened, and they said they felt comfortable around him."