Characters
Mark Renton – the main character and antihero of the novel, Renton is the voice of (relative) sanity among his group of friends, many of whom he cannot stand. He narrates his daily life – from supporting his heroin addiction with dole money and petty theft to interacting with the "normal world" – with a cynical, black-humoured eye. He is capable of fitting in well enough to common society, is relatively good-looking and of above-average intelligence, but is misanthropic and depressed, and uses heroin both as a means to withdraw and to give meaning to his life. Despite his dislike of animals, he is a vegetarian, and unlike most of his circle an avid reader, at one point being caught for shoplifting political theory books.
Simon "Sick Boy" Williamson – A slick, promiscuous, amoral con artist, and Renton's oldest friend. He picks up women with ease on account of his handsomeness and facile charm and flaunts this quality in front of his friends. He is often on the lookout for potential scams, and despite his friendly, charming facade, he generally regards the women he seduces, who he often subjects to confidence tricks, with little more than contempt. By the end of the novel, he has become a pimp of young girls. He also practices blackmail and makes a hobby of shooting dogs. Essentially, a combination of Byronic hero and villain, he becomes even more immoral after the death of his daughter Dawn, who asphyxiates while her mother Lesley and Sick Boy are on a heroin binge (Sick Boy outwardly denies parental responsibility until years after the fact, but it is heavily implied that he blames himself for Dawn's death). Sick Boy considers himself above everyone he interacts with in terms of restraint, and moral fibre, despite being one of the most shallow and callous characters in the novel. It is revealed throughout the novel that even the psychotically violent Begbie at times has a superior moral compass. When thinking to himself, he often imagines he is speaking with Sean Connery. While Begbie represents unavoidable, unanswerable violence to the antihero of the novel, Sick Boy represents cold, calculated expediency, the type of life that Renton would have if he had no conscience or moral restraints. In spite of his apparent sociopathy he has historically shown himself to have been more disciplined in terms of substance abuse than Renton, having gone through a period of alcoholism once during withdrawal from heroin, but still having found it easier than Renton to come off it at various times, and Renton believes he gets pleasure from reminding him of the fact.