A Fulton County Superior Court Judge sentenced a 28-year-old Atlanta man to life plus 15 years Monday for the 2010 murder of popular market owner Baik Sung.

Sung's son James Sung scoffed aloud as a forensic psychiatrist suggested that Oderrick Boone's ingestion of two Ecstasy pills before killing the southwest Atlanta shopkeeper led Boone to "hallucinations" and "disinhibited behavior."

The younger Sung left the courtroom when Boone tearfully read the apology letter he had written days after he killed the store owner.

"I did a bad thing to a good person," Boone said, his voice shaking to prevent crying. "Nothing can justify my actions."

Baik Sung, 62, was killed on July 1, 2010 inside his Westview Drive supermarket.

Surveillance video captured Boone repeatedly stabbing Sung, even dropping a bottle of beer that that the store owner had given him, prosecutors said.

After the victim fell to the floor, Boone stole money from a cash register, left the store and then returned -- stepping over the dying Sung and walking through a pool of the man’s blood -- to steal cigarettes and other goods before leaving the store a second time.

Boone pleaded guilty in early May to murder, felony murder, aggravated assault, armed robbery, theft by taking and possession of a knife during the commission of a felony.

Prosecutors asked for life without parole, while Boone's defense attorney Jennifer Lubinsky asked the judge to give him "a chance to make up for what he'd done."

Judge Jerry W. Baxter said he had a hard decision to make.

"I'm torn," the judge said before making his decision. "I know the family representative here is not of the mind to have any forgiveness, and I feel like once [Boone] woke up from [the drugs], he was remorseful.

"But I watched that man's life blood drain out on the floor and I saw you, Mr. Boone, going to the cash register and stepping over him. You do have hope at the end of the tunnel, but what you did was unforgivable."

Boone will be eligible for parole in 45 years.

James Sung declined to comment after the sentencing, but a letter he wrote was read during the hearing by a county victim's advocate.

In the letter, the 21-year-old described how losing the family's sole breadwinner just two years before he planned to sell the store and retire had put a hardship on himself, his brother and his mother, Baik Sung's wife.

"The atrocious crime committed by Mr. Boone has literally ruined our lives," James Sung's letter read.