A teenage girl who was sexually assaulted and pimped out by Matthew Lallis of Groton told her story in New London Superior Court Thursday before Lallis, 30, was sentenced to nine years in prison.

She was 15 and was having problems at home and in school when Lallis approached her at the Dunkin’ Donuts where he worked. He acted as though he understood her problems, she said. He told her she was beautiful. He knew exactly what to do, and before she knew it, she was locked up in a hotel room, all day.

According to prosecutor Lawrence J. Tytla, the victim, who ran away from home in April 2010, was found near the Super 8 motel in Groton, where she had been staying with Lallis. He had advertised her services on Craigslist, emphasizing her youth, and collected money for her sexual encounters with others, according to Tytla. Lallis also had several sexual encounters with her himself.

“I felt so dirty,” she said. “I will never get over that feeling of being dirty.”

While he was being held at the Corrigan-Radgowski Correctional Center in September 2011, a fellow inmate told state police that Lallis had asked him to kill the victim so that she would not be able to testify against him. The inmate said Lallis told him, “I want you to snuff her for me.”

Lallis pleaded guilty in March to second-degree sexual assault, promoting prostitution and two counts of violation of probation.

The teen is back at school and is reuniting with her family. She missed a lot, she said, but is determined to “show other girls there is a second chance at life.” She came to New London Superior Court with a counselor and her mother. She walked out, upset, before the hearing was over, but not before she asked the judge to impose a protective order and to prohibit Lallis from having contact with children.

Lallis’ attorney, Peter E. Scillieri, said the victim obviously suffered very real pain and trauma, but that she was giving Lallis too much power by ascribing all of her misery to him. The victim’s mother became angry after Scillieri said there was “far, far more going on in her life before this happened.”

Scillieri said Lallis implicated himself immediately after he was confronted by police. Lallis said he didn’t come from a family of criminals and that he needed to understand “that it is time to grow up,” Scillieri said.

Judge Patrick J. Clifford imposed the sentence of nine years in prison followed by three years of special parole. He ordered Lallis to register as a sex offender for 10 years following his release from prison and issued a standing criminal protective order prohibiting him from having contact with the victim.

“She may have had some issues, but you took her childhood away from her and did some damage,” Clifford said. “She (was) 15. She’s certainly going to be in her own prison for years to come.”

k.florin@theday.com