Johnny Rose is a Character and Budding Serial Killer in DEXTER. He along with his girlfriend Nikki Wald are responsible for a series of murders dubbed the Vacation Murders, thus dubbing them both as "The Vacation Murderers".
Johnny is a young, Caucasian man with long shaggy black hair. He wears a green and brown camouflage shirt with a pair of red shorts with what appears to be brown shoes.
He contracted syphilis from an unknown female companion. As referenced from his specific brand of syphilis, he has had multiple partners even while he was with Nikki. It is clear that he didn't get it from Nikki as her name is not in the database suggesting he cheats on her a lot.
He first met Nikki in high school and began a shoplifting crime spree before the fourth season where he was eventually caught with her and later she testified against him for a reduced sentence. At some unknown point in time Johnny and Nikki rekindled their romance and made a plan to rob people so they could buy a boat and sail off to Bermuda. They would later become famous for these crimes as they tended to target tourists, thus earning them the nickname "The Vacation Robbers".
This series of crimes later escalated to murder after one of their victims interrupted them and was incidently killed in the struggle. After this incident they changed their way of operating, beginning a new spree of killings that got their nickname changed to the "Vacation Murderers". Soon after they committed another murder and took every thing they could find, but later the law caught up to them after Johnny accidently cut himself on a cactus leaving blood evidence. Because of this Lieutenant Maria LaGuerta and Sergeant Angel Batista come to Nikki's apartment to question her when Nikki and Johnny were just getting home where they opened fire on the officers and took off in a gray sedan.
It is not until the fifth episode of the season that Johnny becomes the victim instead of the perp after he and Nikki are suspected of gunning down Frank Lundy and Detective Debra Morgan with Lundy dead and Morgan alive. Segerant Batista takes advantage of a reporter, Christine Hill, by telling her about Johnny's syphillis and multiple partners in an attempt to cause a rift in their relationship. When Nikki sees the news article however, she overreacts due to her meth addiction and ends up killing Johnny, ending his reign of terror over the tourists in Miami.