The final moments of Christina Carlin-Kraft’s life were brutal and excruciating, prosecutors said Monday at the start of her alleged killer’s murder trial — a form of “sick, demonic torture” by a man she had met only hours before.

In his opening statement to jurors in a Norristown courtroom, Assistant District Attorney Roderick Fancher said Jonathan Harris, 31, strangled Carlin-Kraft after a violent struggle in her Ardmore condo last summer. He then lied to police, Fancher said.

“His story was that it was over cocaine, but given the circumstances around this murder, it makes no sense that this was about drugs,” Fancher said. “Was it over sex? Was it over money? We won’t know, because the only person who did know was killed in that bedroom that night.”

Harris, who confessed after his arrest, has been charged with first-, second-, and third-degree murder. Assistant District Attorney Brianna Ringwood, the lead prosecutor, has said she is not seeking the death penalty.

Harris’ attorney, A. Charles Peruto Jr., told jurors Monday that there is no question that his client killed Carlin-Kraft, 36, a budding model whom he accompanied home from Center City.

But Peruto contended that Harris went home with her without any intention of harming her, and was “out of his mind" from smoking ketamine. The attorney noted that both Harris and Carlin-Kraft had been drinking throughout the night, and things escalated after Carlin-Kraft refused to pay for an ounce of cocaine Harris gave her.

“I want the jury to listen to the evidence and base their verdict on the evidence, and not what they saw in the press leading up to this,” Peruto said after the proceedings in front of Common Pleas Court Judge William R. Carpenter.

Harris was arrested in August, about a week after Carlin-Kraft’s body was discovered in her unit in Cambridge Square condominiums.

Alex Ciccotelli, Carlin-Kraft’s boyfriend, testified Monday that he hadn’t heard from her for about 24 hours, a break in her normal behavior that worried him. His anxiety worsened after a security system in the condo sent updates to his smartphone showing activity in the unit until 5 a.m.

When he went to the condo to check on her, he found that the door had been latched from the inside. Police officers responding to the scene broke down the door and found the place in disarray, with blood splatters in the kitchen and master bedroom.

On the bed, they found Carlin-Kraft, her body wrapped in a bundle of clothing and bedding that investigators likened to a “cocoon.”

After his arrest, Harris confessed to killing Carlin-Kraft, telling investigators the two had consensual sex, drank multiple bottles of wine, and used cocaine. When Harris asked for payment for the drugs — which he estimated as being worth $1,200 — Carlin-Kraft allegedly refused, sparking a struggle in which she struck him with a wine bottle and he pummeled her multiple times.

Peruto said that refusal enraged Harris, likening him to a “mad dog." In his confession, Harris said he choked Carlin-Kraft to keep her from screaming and left the apartment by jumping over the attached balcony. Harris told police that he thought she was still alive when he left.