But Pieron's life ended abruptly hours later, when police say someone entered his house and murdered the Los Angeles native.
The Miami-Dade Police Department characterized Pieron's death as a homicide Monday, but they have not said how he died nor indicated a possible motive behind the killing. Police would not say whether there was any evidence the murder suspect broke into the house.
"We haven't gotten any information on cause of death at this time," Detective Alvaro Zabaleta, a Miami-Dade police spokesman, told ABC News. "That does not mean they don't know."
Pieron's body was found Saturday by a female friend who arrived at his house for a lunch date. She ran to a neighbor's house seeking help; the neighbor then called the police, shortly after 2:30 p.m.
"It was such a massive amount of blood," the neighbor, Ricardo Silva, told ABC News' Miami affiliate WPLG-TV. "That image is going to stick with me for a while."
"As I walked into the house, I looked to my left and saw the young man on the floor in a rather large pool of blood," Silva told WPLG. "Blood on the couch, blood on the floor."
WPLG also reported that Pieron had been stabbed several times. Authorities would not comment on the cause of death, nor on the specifics of a report in this morning's Miami Herald that Pieron's house was hit in a May robbery in which multiple men with guns entered the house and robbed the roommates of about $600. Zabaleta did confirm that the house recently had been targeted recently in a crime.
Authorities also released surveillance footage of Pieron shopping inside a local CVS store Saturday sometime between 12:45 p.m. and 1:15 p.m. -- less than two hours before his body was found.
The video shows the California native and biology major in a button-down short-sleeved shirt and by himself as he buys a few items, including what appears to be an 18-pack of beer. The newly legal 21-year-old shows the clerk some type of identification for the beer.
"They are hoping to jog people's memories a little bit and see if someone can recall something," Zabaleta, the police spokesman, told ABC News. Another customer may have noticed someone following Pieron inside the store or on his way home, Zabaleta said, describing a possible scenario where the surveillance footage could give investigators a break.
"You think it's nothing at the time, but then this murder occurs and this is the victim," Zabaleta said, "and you're watching the video and you say, 'Wait a minute, I remember seeing that kid.'"
Pamela Bailey, Pieron's mother and a resident of Woodland Hills, Calif., the student's hometown, did not return a call from ABC News but described her son in an interview with the Miami Herald as "gregarious," "outgoing" and "sociable almost to his detriment."
Pieron's MySpace profile, which he last logged in to June 30, detailed a lifestyle perhaps raunchy and rebellious but not threatening or menacing. Among his general interests, he cited "drinkin, smokin, parties, working out, crazy hot sex, chillin with the homies, hackey sack, going to the beach." He listed a range of bands and movies typical of college tastes and called the animated sitcoms "The Simpsons" and "Family Guy" his favorite shows on television.
"I live for the nights I won't remember and the friends I'll never forget," Pieron wrote on his profile, adding that he would like to meet "anybody to waste my day away with."
Miami-Dade police hope to meet -- and arrest -- whoever was behind the brutal killing.
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