Omar is a man of Hispanic descent with black hair and a mustache with beard. He wears a silk orange patterned shirt and a pair of tan pants with black shoes. He also appears to have a tattoo on his right upper arm.
Omar, when he's shown alive, doesn't say a whole lot, but according to Brother Sam he was a man "who got rid of his demons" and was starting out anew. Omar had links to a drug cartel and was likely arrested on possession, eventually going clean as he came out of jail. This suggests that Brother Sam helped him reform and become a normal citizen in society rather than a man dwindling back into a life of crime. Sam is convinced that Omar did not have his death coming, that he didn't deserve to go out that way.
According to Sergeant Angel Batista, Omar Rivera had links to the Salaz Cartel and was likely arrested related to drugs. After he got out of jail, he went to work for Brother Sam before going on to be a fruit vendor and was last seen by Sam a few months before needing new breaks for his pickup truck.
Omar Rivera is seen working at a fruits and vegetables stand beside a busy street in Miami. Little does he realize that Travis Marshall is observing him from a distance. Travis makes his way over to Omar, introducing himself with a verse from the Revelation in the bible: "In the midst of the street was the tree of life, which bares twelve manner of fruit and yielded her fruit every month." Omar didn't really respond to this and instead asked if he needed anything fruit-wise, to which Travis replied with a need for oranges. Omar nodded and repeated the term in Spanish, bending over facing away from Travis to get some oranges for him. While doing this, Travis prepared a large blade from his bag and approached Omar, striking him in the back of the head. He was then dragged down behind the fruit stand and stabbed with the blade, thus ending his life...and from there he was dissected, having his intestines removed and placed on a scale at the stand while they were replaced with seven baby snakes sewn in by the Greek pattern for Alpha and Omega.
His body was later dumped some time after, to wash up on shore on a beach. A nearby jogger screams and calls in the body, and Dexter Morgan and team arrive to investigate. Upon lifting his shirt, they find the strange etching of where he was cut open and pulling out his wallet reveals his name as well as other information. His stomach begins to move and Dexter cuts open some of the sewing, revealing the baby snakes slithering out from the open wound.
Omar becomes the first major victim of Travis Marshall, and the quote Travis told him related to their very location.
- In a newspaper article that Professor James Gellar reads during "The Angel of Death," Omar's name can be read as "Omar Gonzalez" rather than Omar Rivera.