CHARLESTON - She was a young mother originally from the Northeast. He's a registered sex offender with a criminal history that spans 14 years.

Charleston County sheriff's investigators think that Alexis Lukaitis and Darold Drayton drove together from Bluffton to Charleston on Sunday. Only he would return.

Lukaitis was found dead on the side of Old Jacksonboro Road on Monday morning. The 27-year-old mother of twin boys had been stabbed in the chest and throat. Her body was partially clothed, and it appeared someone had tried to burn it, authorities said.

Sheriff's investigators on Thursday charged Drayton, 32, with her murder, a day after he was found in Beaufort County with cuts and scratches on his body and a deep slice wound to his right index finger. An affidavit said investigators found blood-stained evidence from Lukaitis' car behind the Bluffton house of one of Drayton's cousins, who implicated Drayton in the crime.

Michael Bartley, Lukaitis' fiance who reported her missing Monday, told investigators that she told him that she and Drayton were going to Charleston to get prescription pills, according to an arrest affidavit. Drayton told deputies he occasionally gave her pills, the affidavit states.

Family and friends said Lukaitis considered Drayton a friend. Bartley wrote in a text message Thursday that they had no idea of Drayton's extensive criminal history or they would have stayed away from him. Bartley declined to talk about the pills but said his fiancee would take people at their word. "She was doing a favor," Bartley wrote. "She would do that."

Lukaitis did not have a criminal history in South Carolina, according to a State Law Enforcement Division criminal history check.

A Bluffton woman who knew Lukaitis and Drayton said Thursday that the three of them were good friends. She said Lukaitis agreed to drive Drayton to Charleston on Sunday, but she did not know why. The woman, who asked not to be identified, said she and Lukaitis suspected Drayton had been in some trouble with the law before but weren't worried about driving him to Charleston.

"I would have trusted him enough. He was one of our best friends," the woman said of Drayton, whom they called "D." "The D we knew and the D being presented to us now were two different people."

Drayton has three armed-robbery convictions and multiple drug convictions dating back to 1996. He was placed on the South Carolina registered sex offender's list in 2005 after he was convicted of committing a lewd act upon a child under 16, according to a SLED background check.

The friend said Drayton told her and police that he had nothing to do with Lukaitis' death. He told her that Lukaitis never showed up to his house to drive him to Charleston, the friend said.

Bartley, Lukaitis' fiance, told Beaufort County sheriff's deputies that she left the house about 3 p.m. Sunday to drive a friend to Charleston.

Authorities said Lukaitis called Bartley about 7:45 p.m. Sunday and told him she was about an hour away from home. That was the last anyone heard from her.

Loggers found her body about 12 hours later. She had defensive wounds on her hands and dirt and skin beneath her nails, indicating that she attempted to fight back, authorities said.

Her white 2001 Pontiac Grand Prix was recovered Wednesday morning in a restaurant parking lot on Bridge Street. Blood was found on the outside and inside of the car, including in the trunk, an affidavit states. The spare tire, foam insert and trunk liner were missing from the trunk.

Police said they later found the missing items with blood on them in the backyard of Drayton's cousin's house. The cousin, who is not charged in the case, told police that Drayton arrived at his house about 7:30 a.m. Monday and asked to be taken to the hospital for a cut on his hand that he suffered in a fight.

Beaufort deputies tried to talk to Drayton on Monday but he refused to speak with them, Sgt. Robin McIntosh said. They found him Wednesday outside the Bluffton Library and arrested him on an outstanding warrant for failure to register as a sex offender. He also was cited for simple possession of marijuana.

By Thursday afternoon, Charleston County sheriff's deputies had a warrant in hand and were taking it to a magistrate to be signed.

Reach Andy Paras at 937-5589, aparas@postandcourier.com or on twitter at twitter.com/andyparas.