In a hospital room in Center City, Jonathan Harris told the man in the next bed that there “is nothing like squeezing somebody and feeling the last breath leave their body,” the man told jurors Tuesday.

Harris, 31, is charged with murder in the slaying of Main Line model Christina Carlin-Kraft, whom he told police he strangled amid a violent encounter in her Ardmore condo last summer.

During the second day of testimony in Harris’ trial, Brandon Pearson recounted a conversation with Harris inside Penn Presbyterian Medical Center in the days after Carlin-Kraft’s death. Harris ended up there after fleeing into the city from the scene of the slaying, eventually getting arrested by Philadelphia Sheriff’s Office deputies for acting “aggressively and erratically," investigators said.

Jurors listened intently as Pearson recalled Harris’ shocking words.

Earlier in the day, another witness cast doubt on Harris’ version of the events that led up to Carlin-Kraft’s death.

Harris, a Johnstown, Pa., native, said he met Carlin-Kraft in Center City and went back with her to her condo in Ardmore to sell and use an ounce of cocaine, and they ended up having consensual sex. His lawyer, A. Charles Peruto Jr., told jurors Harris snapped when Carlin-Kraft refused to pay for the drugs, which he estimated as being worth $1,200, and the dispute escalated to blows.

But Khalil Wardack, the medical examiner who performed Carlin-Kraft’s autopsy, testified Tuesday that she had no illegal substances in her body at the time of her death. She only tested positive for alcohol, Wardack said, with a blood-alcohol content of 0.252 percent, three times the legal definition of drunken driving.

In his testimony, Wardack said the numerous injuries to Carlin-Kraft’s body included neck fractures that would have required more than 33 pounds of pressure to inflict. He ruled that the cause of her death was strangulation, most likely with a pair of green sweatpants that investigators found inside her condo.

Carlin-Kraft and Harris met each other in the predawn hours of Aug. 22, crossing paths in Center City, investigators said Tuesday.

Prosecutors re-created the paths the two took that morning, leading jurors through more than 10 minutes of footage from surveillance cameras. The video showed Harris emerging from a SEPTA station near City Hall just after 2 a.m., and then walking south on Broad Street. A few minutes later, Carlin-Kraft arrived in a ride-share vehicle, and the two met outside a pizza shop on 13th Street.

They walked together for about 15 minutes, at one point arm-in-arm, before getting into a waiting vehicle.

Andrew Sanford was behind the wheel of that vehicle, which he drove for Lyft. He testified Tuesday that Carlin-Kraft flagged him down as he was driving on Broad near Locust Street and begged him for a ride. He said she told him she was being harassed on the street by several men, and that she wanted to get home to safety. She told Sanford that Harris had helped protect her from those men.

After some coaxing, Sanford agreed, and Carlin-Kraft pulled Harris into the vehicle with her, he said. Inside the vehicle, the two passengers were “affectionate," with Carlin-Kraft kissing Harris and seeming to initiate most of the contact.

The ride was uneventful, he said, with Harris staying quiet and Carlin-Kraft displaying a “happy-go-lucky” attitude.

“I figured she had just gotten done partying, and wanted to go home with him and do whatever they planned on doing together,” Sanford said.

When they reached the Ardmore condo building, Carlin-Kraft rushed inside, saying she had to use the bathroom, he said. Harris offered the driver $100 if he waited outside, saying he didn’t plan to stay long and would be back for a ride home within 10 or 15 minutes. He exchanged phone numbers with Sanford.

When 20 minutes went by with no word from Harris, Sanford said, he called Harris, but the call went to voice mail, so he drove back to Center City.