Blacksburg, Virginia (CNN) It's perhaps one of the most persistent queries surrounding the horrific slaying of Nicole Lovell , a case that seems to produce more questions each time an answer surfaces.

Why would a Virginia Tech engineering student and theater geek with a history of strong grades and extracurricular interests -- and no delinquency in her background -- allegedly help plan and obscure the 13-year-old girl's killing?

To be sure, these are mere allegations against Natalie Keepers, who faces a count of concealing a body and counts of accessory to murder before and after the fact. Keepers has yet to enter a plea, and her attorneys have declined repeated requests for comment.

Whether the accusations are true is something that will be determined in what could be a lengthy and high-profile legal proceeding. Still, police and prosecutors have leveled a series of allegations that suggest the 19-year-old with a promising future helped a man with whom she had no apparent romantic connection commit and conceal a cruel crime simply for the novelty of it.

While a law enforcement official has told CNN that David Eisenhauer engaged in an inappropriate relationship with Nicole and stabbed the girl to death when she threatened to expose their relationship, Keepers' alleged motive hasn't been so clear.

School stress, depression

Keepers took the stand Thursday in a failed bid to convince Judge Robert Viar Jr. to grant her bail. There, she revealed much about her past. Her upbringing, mental health issues and high school achievements were among the topics of her testimony.

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With Nicole's mother on the courtroom gallery's front row, and the girl's father right behind his ex-wife, his arm in a sling, Keepers sat before Viar with her hands shackled at her waist, wearing a burnt-orange jumpsuit with "WVRJ inmate" on the back, short for Western Virginia Regional Jail. She told the judge her gluten allergy hadn't been accommodated during her five days in jail, where she was being held in isolation.

She went on to testify that she'd graduated among the top 15% of her class at Hammond High School in Columbia, Maryland. She described her interests as math, science and theater.

She was on the editorial staff for Hammond's literary magazine, and social media posts show she was assistant director for the school's performance of "Almost, Maine" in November 2014. She performed in "Rumplestiltskin" in May, and before arriving at Virginia Tech, she appeared in a public service-style video decrying unemployment among college graduates.

Hammond Theater Assistant Director Natalie Keepers prepares for another day of rehearsal of #AlmostMaine next Thu-Sat pic.twitter.com/hYCOK4BQLT — The Bear Press (@hhsbearpress) November 5, 2014

"I believe I did as well as I was able to," she told Viar of her short time at Virginia Tech.

Elaborating, she said she had issues transitioning from high school to college, and a psychiatrist at Virginia Tech's Cook Counseling Center had prescribed her 40 milligrams of Prozac to combat depression along with another medication to lessen the intensity of her anxiety attacks.

The doctor was considering upping her Prozac dosage to 60 milligrams "to make sure my anxiety wasn't getting ahead of me with all the hard classes I was taking," she said.

"Since I have been on the Prozac, I have not had any issues with my depression," she said, adding that the jail staff had begun providing her 20 milligrams the day before the bond hearing.

She said her last visit to Cook Counseling Center came in December, but because of the medications she's on, she would need to have checkups every few weeks.

Her battle with self-harm

Keepers' mental health issues started when she was in eighth grade, according to her testimony.

"I was dealing with a lot of bullying issues so I started cutting myself," she said.

She never attempted suicide, but she thought about it "a few times" in eighth grade. For about a year and a half stretching into ninth grade, she said, she saw a Christian counselor in Columbia who taught her stress-reduction techniques, such as writing, ripping paper, singing and drawing.

The self-harm continued until 2014, when she and a friend made a pact: If they got through all of 2015 without cutting themselves, they would get tattoos of semicolons.

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Where a period represents the conclusion of a sentence, Keepers said, the tattoo behind her right ear means that "instead of putting an end to my story, I chose to continue it," and she further made a promise to God, her family and the world that she wouldn't do "anything suicidal ever again."

"I've learned, especially after counseling, how to love myself," she testified.

Her father, Tim Keepers, took the stand and described Natalie as a normal teenager who liked Swedish Fish candy and was once a member of a Disney princess club, a piece of testimony that drew his daughter's only smile during the hourlong hearing.

For most of the hearing, Natalie Keepers sat between her lawyers, her wavy brown hair blocking her face from the gallery, which consisted mostly of media, police and Nicole Lovell's family. As her father testified, she lifted her hands, still shackled to her waist, onto the defendant's table and let her fingers dance as if she were typing or playing piano.

She broke down as her father spoke and occasionally looked through pink, puffy eyes and glasses into the crowd, her lips in a slight pout.

After Tim Keepers explained how his daughter had never had any disciplinary issues before this year, he, too, broke down when asked about Natalie's ambitions in life.

"She wanted to follow ..." he began before choking up and quickly composing himself. "She wanted to follow in my footsteps and be an aerospace engineer."

His daughter excelled in school, he said, but would sometimes find herself overwhelmed by project deadlines. The Keepers home is a place where "education comes before chores," he said, but sometimes he would have to remind her that every effort need not yield an A.

"I would have to caution her, you know, 'B's are OK,' " he said.

Parents knew of Eisenhauer

As for their daughter's acquaintance with Eisenhauer, both Tim and Sara Keepers said they were aware the two were friends. Tim Keepers said he first heard Eisenhauer's name in October or November.

However, he said he didn't know the two were "that close," despite testifying earlier that it was Eisenhauer who "dropped everything to rush her to the hospital" when Natalie needed an appendectomy.

"He was very worried about her," he told the judge.

Both parents said they were devastated to learn of their daughter's arrest. They had no idea she might be involved in an alleged murder plot, they said, and Tim Keepers described being confused and incredulous and thinking, "Not my daughter."

"It's kind of like when you get punched in the stomach by someone who is much bigger than you," he said.

Tim Keepers told the court he had roughly $55,000 in liquid assets and would "absolutely" be willing to dip into the family's home equity and retirement funds to secure his daughter's release on bail.

Asked if he would follow all the bail requirements, he replied, "That's my job, and that's how I live my life. ... I promise I will obey."

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The family home -- which includes Natalie's sister, twin brothers and two dogs -- is close, happy and Christian, he added.

If granted bail, Natalie would stay at the two-story, brick-and-siding home with a two-car garage, located in a cluster of $500,000-plus houses off Interstate 95, roughly halfway between Washington and Baltimore.

Sara Keepers is an X-ray technician with a flexible schedule and would be around to keep an eye on her daughter while she was under house arrest, should she be granted bail, her father testified. Her grandparents also live nearby, he said.

The line of cross-examination from Pettitt, the prosecutor, at first seemed to bolster the defendant's case for bail. She repeatedly asked questions similar to those from the defense attorneys.

Did counselors believe Natalie Keepers was dangerous? Was she ever a problem in the past? Did her parents know about her alleged involvement in the Nicole Lovell killing, or was it a "complete surprise"?

Nicole's 'Minions' blanket found in dorm

In closing arguments, though, Pettitt laid out myriad details -- some new, some old -- providing a rough outline of the teen's alleged involvement in Nicole's killing. Among them, according to Pettitt:

• Keepers went to a Cook Out restaurant in Blacksburg with Eisenhauer to discuss the plot and also drove by Nicole's home with him.

• Part of the plan they discussed involved a ruse in which Eisenhauer would take Nicole to a remote location under the guise of a romantic date and "cut her throat."

• Keepers and Eisenhauer bought a shovel to dispose of Nicole's body.

• Eisenhauer denied involvement in the killing but acknowledged that he had chatted online with Nicole before her disappearance. He then drove to the 13-year-old's house around 12:37 a.m. on January 27 where he watched Nicole exit her bedroom window and "gave her a side hug" before paying a visit to Keepers.

• After Eisenhauer told Keepers on January 27 that he'd killed Nicole, Keepers "helped him load Lovell's remains into the trunk of his Lexus."

• Keepers and Eisenhauer then went to a store to buy cleaning supplies with Nicole's body still in the trunk. They later dumped the body just over the state line in North Carolina.

• When police knocked on Keepers' boyfriend's door to question her, she sent a text to Eisenhauer: "POLICE."

• During questioning, police felt she was holding back. Keepers became emotional and told police, "I don't want to go to jail," waived her rights and began cooperating. Nicole's "Minions" blanket and the cleaning supplies Keepers and Eisenhauer had bought were found in a suitcase in Keepers' dorm room.

• Keepers also provided information on the murder weapon, Nicole's remains and Nicole's clothing.

Pettitt did not rebut the defense assertion that Keepers is not accused of Nicole's actual murder, but the prosecutor said the law makes little distinction between committing a murder and being an accessory before the fact. They're both punishable by life in prison. (Eisenhauer, 18, stands accused of murder and abduction. His attorney has declined repeated CNN requests for comment.)

The case for keeping her in jail

Pettitt's cross-examination tack became clear as she appeared to outduel the defense during closing arguments, saying neither ankle monitoring nor Keepers' parents' promise to keep a close eye on her would keep the community safe.

Virginia Tech's Cook Counseling Center -- which came under a microscope in 2007 after it was revealed that the shooter in the Virginia Tech massacre that killed 32 people had been treated there -- had no idea Keepers was homicidal, the prosecutor said. Her parents were oblivious that their daughter was allegedly involved in a murder plot, she said.

Furthermore, Keepers' only connection to the Blacksburg community is Virginia Tech, and she's been banned from campus, Pettitt said.

Based on those factors -- as well as the fact she's accused of helping plan the murder of a girl she didn't know -- there is "no possible combination of terms of bond that would be reasonable to release her back out to a community that has never met her," Pettitt said.

Keepers' attorney John Robertson argued that his client cooperated with law enforcement, which "led to material evidence. She provided the assistance, your honor."

But the judge wasn't convinced, and deputies escorted Keepers back to the jail, where she will likely stay until her trial begins. Following the hearing, Tim Keepers took his wife's fingers and intertwined them with his own. Sara Keepers stood close behind him, her head down, as police allowed Nicole's family to exit the courtroom first.

Tim and Sara Keepers then briskly walked hand in hand to an adjacent courtroom, the media behind them. They provided no comment.