MIAMI (CBSMiami) - Testimony resumed Wednesday morning in the trial of a man accused of killing an 18-year old University of Florida student from Miami.
Pedro Bravo, 20, is charged with first degree murder in the 2012 death of Christian Aguilar.
During his opening statement, prosecutor Brian Kramer told the jury that Aguilar's murder "was about the elimination of a rival fueled by jealousy, hatred and anger."
Among the items presented to the jury was Bravo's journal/sketch book in which, Kramer claimed, he obsessed over his ex-girlfriend Erika Friman who had started to date Aguilar.
The letters included one with the face of a devil on it. There were other sketches, and one letter, prosecutors say, was a suicide note Bravo wrote in prison.
"With everyone out there wanting blood, wanting me gone, I will give them what they want," Bravo wrote. "I'm glad I am hated now in a sense everyone thinks of me negatively so when I'm gone I will not weigh heavy on people's hearts. I will not be missed."
In the letter Bravo admits to fighting with his friend.
"I am a monster for having hurt Chris the way I did," Bravo wrote. "I am a monster for having hurt Chris the way I did…I spend every day going back in time to have taken my life before anything happened."
Prosecutors say Bravo was jealous that Friman, his girlfriend in high school, had broken up with him and was dating Aguilar.
One passage read, "All this time, all these girls I've seen, all who talked to me and I still want you. Its been so long and I still want you. You were mine and I was yours, now I am just yours."
Another noted, "I want to give up everything to be with her again."
On the stand, Friman testified that she and Bravo dated for three years in high school and the end of their dating relationship was hard for him to accept.
"I was concerned he was having trouble getting over me based off the emails and text messages, but I was hoping he was doing fine in Miami," said Friman.
Aguilar, Bravo and Friman all attended Doral Academy.
Friman said at one point she reached out to Bravo after he talked about suicide in an effort to "try and calm him down," according to CBS4 news partner The Miami Herald.
Friman testified that she never told Bravo about her new relationship with Aguilar because she didn't want to "push him over the edge."
"I lied to him," said Friman. "I didn't think he was ready to hear that at that time."
When the two met face to face later, Friman said Bravo really wanted to get back with her but she was adamant, "I told him I was not interested."
Friman said after talking with Aguilar about Bravo's behavior, he agreed to help talk him through his "depression issues," according to the Miami Herald.
The day he disappeared, Friman said she expected to meet Aguilar after class. She said grew more concerned after she couldn't reach him after repeated calls and texts.
Friman said when she finally got a hold of Pedro and asked him if he had seen Aguilar, he strangely claimed that he had dropped Christian off by a YMCA.
When she reported Aguilar missing to the Gainesville police, Friman said Bravo seemed "surprised" when she mentioned that Christian was her boyfriend.
The prosecutor then had her identify several of Aguilar's personal items including his toothbrush, which was used for a DNA sample, and his backpack which was found in Bravo's closet.
After a recess, Friman returned to the stand for the state.
The prosecution showed a copy of a journal entry by Bravo on a television screen which read "A problem has occurred, you need an alibi," according to the Miami Herald.
They also had Friman read from what the called a possible suicide letter penned by Bravo in which he wrote "I am a monster for having hurt Chris the way I did."
In the letter, Bravo made no admissions to murdering Aguilar but he did write "I hope they find Chris .. sad to live in a world where you are guilty until proven innocent."
Friman also read from a letter written by Bravo in which he describes a scenario in which three to four people are killed and Aguilar's murder would be pinned on a serial killer. The letter, written to a fellow inmate, said the "individuals must be strangled and Tasered" and he'd pay $1,000 for each body, according to the Miami Herald.
The prosecution also had Friman read from another letter Bravo wrote to her but never sent.
"You're the greatest person on this bloody earth, I won't let you fall."
After conferring with his client, Bravo's attorney elected not to cross examine Friman.
During his opening, Kramer also showed the jury surveillance pictures of Bravo buying a shovel, duct tape, sleeping pills and knife.
Bravo, a former Santa Fe College student, is accused of killing Aguilar sometime after the two were captured on surveillance video at a Gainesville Best Buy on September 20th, 2012.
Kramer said Aguilar was killed in Bravo's car in a Walmart parking lot by strangulation; it took 13 minutes.
Kramer said Bravo may have strangled him with a belt found in the backseat which had Aguilar's DNA on it. There was also an empty Gatorade bottle in the car.
"This bottle contains dyphenhydromine and acetaminophen. Those are the same contents of the Z-Quil that is cut open and of the Equate that has been separated and emptied. That is planning to poison someone, " said Kramer.
It wasn't until October 12th, following a massive volunteer search, that Aguilar's body was discovered by hunters deep in the woods. His body was half-buried in Levy County, an hour from the UF campus.
During the course of their investigation, police found a receipt showing Bravo purchased a shovel and duct tape just days before Aguilar's disappearance. They also found blood in Bravo's SUV.
Kramer pointed out that duct tape was found next to Aguilar's foot and his wrists were bound to his neck with tape as well. He added that Bravo revealed the location of the shovel to an inmate who turned it over to investigators.
In his opening statement Bravo's defense attorney, Michael Ruppert, told the jury that Bravo and Aguilar got into an argument in a wooded section near where his body would later be found. He said Aguilar told Bravo 'why don't you just kill yourself'. The two fought and Bravo left Aguilar bloody but conscious.
Ruppert said while his client may have been suicidal and depressed over his ex-girlfriend, he did not have premeditation to kill.
"Pedro was wrong for getting into a fight with his friend. Pedro was wrong for leaving his friend in the condition that he was in but he did not kill Christian Aguilar," said Ruppert.
Bravo is not expected to testify during the trial.
The state is not seeking the death penalty. Bravo could face life in prison.
CBS4 news partner The Miami Herald contributed to this report.
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