Tens of thousands of texts amounting to what prosecutors call months of "wanton and reckless" psychological abuse were presented Friday during the arraignment of a Boston College student accused of prodding her boyfriend to take his own life, then failing to intervene when he did so.

Inyoung You, 21, a native of South Korea who is an American citizen, appeared emotionless as prosecutors in Suffolk County Superior Court in Boston laid out their case for how she allegedly drove her boyfriend, Alexander Urtula, 22, to suicide. You, who is on leave from Boston College, pleaded not guilty to manslaughter and failing to act.

During the 18 months that You dated Urtula, who was also a student at the college, prosecutors say their relationship grew increasingly abusive and You would repeatedly text him to "kill himself or go die."

A grand jury indicted You last month, and Suffolk County District Attorney Rachael Rollins said the texts appeared to become "more frequent, powerful and demeaning," even though You knew Urtula was going through a "spiraling depression."

Inyoung You, a former Boston College student from South Korea, arrives to be arraigned on involuntary manslaughter charges in connection with the suicide of her boyfriend, in Suffolk County Superior Court in Boston on Nov. 22, 2019. Katherine Taylor / Reuters

Prosecutors have alleged that You exerted control over Urtula, tracking his movements via his cellphone and sending thousands of texts in the run-up to his death. Before their relationship began, Urtula had no documented mental health issues, did not exhibit risk factors for suicide or mention self-harm in his journals prior to January 2018, prosecutors said.

In the two months before he took his own life on May 20 — the same day he was to graduate from Boston College — Urtula and You exchanged about 75,000 text messages, with about 47,000 of them coming from her.

At times, You would threaten harm to Urtula, once texting before his upcoming graduation, "I want to bash your head against a wall," and would also claim she was going to harm herself because of him, a tactic that kept him from leaving her, assistant prosecutor Caitlin Grasso said at Friday's arraignment.

The threats would escalate, Grasso added, when Urtula didn't respond to her fast enough, asked for space or wanted permission to go to sleep.

The texts, which prosecutors say were uncovered through a forensic extraction of Urtula's phone, as well as journal entries showed how You allegedly broke down Urtula emotionally and how he grew more and more isolated from his friends earlier this year.

He texted on April 11 to her that "I'll leave this f------ earth just please don't do anything don't hurt yourself anymore" and "I'll go die for you," prosecutors said.

When Urtula attempted to assert himself and accused You of being the abusive one, prosecutors added that she turned it on him, texting on April 29: "ABUSE U THINK I ABUSE U U WANNA SAY I ABUSE U ... UR THAT F------ IDIOTIC AND STUPID REALLY ABUSE."

Alexander Urtula. Suffolk County District Attorney

Two days before his death, Urtula struggled with cutting off contact with his friends at Boston College, which You allegedly asked him to do. In a message sent on May 18, prosecutors say she wrote: "did I NOT F------ TELL U TO READ [MY TEXT] NOW IF YOU DO NOT F------ READ IT RIGHT NOW I'M LITERALLY GOING TO F------ SLASH MY THROAT AND TAKE A VIDEO SAYING IT WAS BECAUSE OF YOU."

Urtula at times would try to stand up for himself. Grasso said he was distraught that one of the people he said "I love most in the world" was telling him to take his own life.

"Stop telling me how worthless and pathetic I am ... and how much I deserve to die," Grasso said he texted on March 31.

Urtula, a biology major originally from Cedar Grove, New Jersey, and a member of the Philippine Society of Boston College, died after authorities say he jumped from the roof of a parking garage less than two hours before he was supposed to walk at commencement.

Prosecutors said You was able to track Urtula to the garage through his cellphone location function that morning, and in a few minutes of her arriving at 8:31 a.m., he jumped.

They allege that she knew he was threatening to harm himself and that "she did not contact law enforcement and medical personnel to intervene and prevent his death," nor tell the parking garage staff who would have been in a position to assist.

During a news conference after her arraignment, You's defense attorney, Steven Kim, blasted the handling of the case as "unjust and callous behavior by a district attorney in what I can only conclude is a cheap pursuit of headlines."

The charge against You, Kim added, is traumatizing to her "but also happens not to be true. When the facts come out, it will be clear that these two young individuals were very needy emotionally and were involved in a relationship that became a toxic blend of fear, anger, need and love."

Kim suggested a jury pool could be tainted because of the intense media attention in the case. He also clarified that You remains a student at Boston College; prosecutors had referred to her as a former student.

Initially, prosecutors said they might need to extradite You from South Korea since she was overseas when the indictment was announced. Kim said that while she was born there, she grew up in suburban Seattle and is a U.S. citizen.

The matter has drawn comparisons to another high-profile case in Massachusetts in which a young woman, Michelle Carter, was convicted of involuntary manslaughter in 2017 after her boyfriend died by suicide.

The case against Carter hinged on text messages in which she appeared to prod her boyfriend, Conrad Roy III, to "take action." Both Carter and Roy suffered from depression, attorneys said at the trial.

The judge at You's arraignment allowed her release on $5,000 bail, an amount arranged with prosecutors because she had voluntarily returned to the U.S. from South Korea to face charges and has no prior criminal record. She must surrender her passport and remain in Massachusetts before pretrial hearings next year.

If you or someone you know is in crisis, call the National Suicide Prevention Lifeline at 800-273-8255, text HOME to 741741 or visit SpeakingOfSuicide.com/resources for additional resources.