A New England prep school student identified a former classmate as the person who raped her last year on campus, but the lawyer for the defendant - who graduated and was accepted into Harvard to study theology - told jurors Tuesday that emails and text messages from the alleged victim will show the encounter was consensual.

Prosecutor Catherine Ruffle said in her opening statement that Owen Labrie, of Tunbridge, Vermont, raped the 15-year-old girl at a campus building at the prestigious St. Paul's School in Concord.

"This case is about Owen Labrie sexually assaulting a 15-year-old girl," Catherine J. Ruffle, the deputy county attorney, said in court, according to The New York Times. "It's about how he thought about this for months. How he made a plan."

Labrie, now 19, has pleaded not guilty. He denied ever having sex with the accuser and reportedly called their encounter consensual.

The accuser broke down crying Tuesday while on the stand and pointed at Labrie when asked if he was in the courtroom. The petite student, her ash blonde hair pulled back from her forehead, told jurors the two weren't friends and he was a classmate of her older sister.

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She said she thought his invitation to a Senior Salute was "disgusting" because it was written so sappily.

"I thought his intentions were really wrong," she said, but she reconsidered when a male friend persuaded her. The teen said Senior Salute was well known on campus but she didn't think it involved any special expectations.

Defense lawyer J.W. Carney said Labrie will testify he had consensual sexual contact with the girl two days before he graduated last year but they did not have intercourse. Carney told jurors that email and Facebook exchanges between the two will show the girl met Labrie, who was 18 at the time, willingly and bantered with him after their encounter.

Carney, who minimized the Senior Salute element, read to jurors from a string of emails between the two before and immediately after the encounter. In them, the girl agreed to meet Labrie "only if it's our little secret."

In an email exchange after the encounter, Carney told jurors, she wrote: "You're not so bad yourself. I also lost my earring up there."

"Does this sound like texting where she is unwilling that night?" Carney asked.

"When you've seen all the evidence, had a chance to study these emails and text messages and you've had a chance to hear from Owen himself, you will have reasonable doubt about what happened," Carney said.

Ruffle said the girl would testify the two had removed some clothing and were kissing when Labrie became more assertive. The girl said no and clutched her underwear with both hands to try to stop Labrie, but he forced himself on her, Ruffle said.

"She's going to testify the defendant became very aggressive, very fast," Ruffle told jurors. "He pulled her bra down, he bit her breast and it was painful."

"She's a 15 year-old girl without sexual experience," Ruffle said. "She tried to say no, tried to use her physical conduct to let him know this was not OK."

After opening statements, jurors visited the campus at St. Paul's, whose alumni include Secretary of State John Kerry. Doonesbury creator Garry Trudeau also is an alum, as are 13 U.S. ambassadors, three Pulitzer Prize winners and sons of the Astor and Kennedy families. The school enrolls about 530 students and admitted girls for the first time in 1971. Tuition, room and board costs $53,810 a year.

"Allegations about our culture are not emblematic of our school or our values, our rules, or the people that represent our student body, alumni, faculty and staff," read a statement on the school’s website.

According to police affidavits, Labrie spoke freely about the Senior Salute and about a contest in which seniors tried to have sex with the most underclassmen. He said that as a student leader he tried to educate others against the practice.

Prosecutors, however, said that Labrie and friends would refer to "slaying" girls and said he told police that he was trying to win the competition on how much he could "score," The Times reported.

He was given the Rector's Award at graduation for "selfless devotion to school activities."

Ruffle also told jurors that Labrie on March 31, 2014, made a list of girls he considered for "possible Senior Salutes" and the only name in capital letters was that of the accuser.

Carney said after court he's looking forward to his chance to question the accuser.

The trial is expected to last two weeks.

Fox News' Molly Line and The Associated Press contributed to this report