Dexter "Dex" Morgan (born Moser) is the main character and narrator of the series. Dexter is a forensics expert and blood spatter analyst employed by the Miami Metro Police Department, but has a double life as a serial killer. As young boys, he and his older brother Brian witnessed the murder of their mother, Laura Moser, and were left for two days in a shipping container filled with blood. The incident left them psychologically scarred. Soon afterwards, Dexter was adopted by Harry Morgan, who hoped to help repress his memory of the death of his mother. However, he soon realized that Dexter had an insatiable urge to kill that would begin to intensify. Harry, frustrated with the number of people who avoided justice, decided to train Dexter as a killer who would target and dispatch other murderers.
Dexter considers himself emotionally divorced from the rest of humanity; in his narration, he often refers to "humans" as if he is not one of them. Dexter makes frequent references to an internal feeling of emptiness, leading to several attempts in his youth to "feel alive". Dexter claims to have no feelings or conscience and that all of his emotional responses are part of a well-rehearsed act to conceal his true nature. In the first season of the television series he had no interest in romance or sex; this changed when he became involved with Lila in the second season. He initially considered his relationship with Rita to be part of his disguise. However, by the end of the fourth season, Dexter had fully evolved into a family man and wished to rid himself of his self-titled "Dark Passenger".
There are chinks in Dexter's emotional armour, however. He acknowledges loyalty to family, particularly his now-deceased, adoptive father, stating "If I were capable of love, how I would have loved Harry."[citation needed] Since Harry's death, Dexter's only family has been his sister, Debra Morgan, Harry's biological daughter. At the end of the first novel, Dexter admits that he could not hurt Debra or allow Brian to harm her because he is "fond of her".
Dexter likes children.[citation needed] The flip side of this affection is that Dexter is particularly wrathful when his victims prey on children.[citation needed] In the book Dearly Devoted Dexter, Dexter realized that Rita's son Cody was showing the same signs of sociopathy as Dexter had at that age, and looked forward to providing him with "guidance" similar to that which Harry provided him. Cody's perceived sociopathy has not been shown in the television series.
This also gives him a reason to continue his relationship with Rita, to whom (as of Dearly Devoted Dexter) he is engaged because of a misunderstanding. At the beginning of the third book, Dexter in the Dark, it is revealed that Cody is not the only one with dark impulses, as Astor too pressures Dexter to teach her. Dexter comes to accept his role as a stepfather to both children very seriously in Dexter in the Dark. For example, while on a stakeout, he begins to wonder if Cody has brushed his teeth before going to bed and if Astor had set out her Easter dress for photo-day at her school. These thoughts distract him while he is waiting for an intended victim, which thoroughly annoys him. In the TV series, Dexter also takes a detour in his code of only killing murderers in order to dispose of a pedophile who is stalking Astor.
Animals do not like Dexter, which can cause noise problems when Dexter stalks a victim with pets. He is quoted as having once had a dog that barked and growled at Dexter until he was forced to get rid of it, and a turtle, which hid in its shell until it died of starvation rather than have to deal with Dexter.
