<P> Critics have praised the character and credit him for much of the show's success . He is considered the show's breakout character . </P> <P> The show's creators envisioned Barney as what Bays later described as a "large, John Belushi - type character"; nonetheless, Megan Branman, the casting director for How I Met Your Mother, invited Harris to audition . He assumed that he was invited solely because the two were friends and did not believe he had a chance of winning the role . Harris later said: "Since I (considered) myself the long shot, I didn't care that much, and I think that allowed a freedom ." His audition centered on a scene playing laser tag, and Harris attempted a dive roll, accidentally knocking over a chair and slamming into a wall in the process . CBS executives enjoyed his playing and soon offered Harris the part . The character is named for a heroin dealer in the James Ellroy novel L.A. Confidential . </P> <P> Barney Stinson is one of five main characters on How I Met Your Mother . He is a manipulative, oversexed businessman in his thirties who always wears a suit, likes women with "daddy issues" and is frequently willing to offer his (sometimes hypocritical) opinion . Throughout the earlier seasons, Barney is a huge womanizer, and has been described as a "high - functioning sociopath" by his best friend, Ted Mosby (Josh Radnor). Barney has a plethora of strategies and rules designed to meet women, sleep with them, and discard them . Through several seasons of the show, four (4) of the main characters are couples, as Ted began dating Robin Scherbatsky (Cobie Smulders) and Ted's roommate Marshall Eriksen (Jason Segel) becomes engaged and later married to Lily Aldrin (Alyson Hannigan). This leaves Barney the only single character, and, according to Harris, Barney is "resentful" that the other characters have paired up . Later on, in season 5, he dates Robin . They end up breaking up not long after, once they both realize they are making one another miserable . </P> <P> Harris describes Barney as a man who "likes to create crazy situations and then sit back and watch it all go down ." He is an opportunist who manipulates any situation so that it goes his way . He is also highly competitive, and will take on "challenges" to complete outlandish tasks in order to prove his worth . He is proud and stubborn, and attempts to stand by his word no matter what . In "I Heart NJ", for example, he refuses to put down his fist unless someone offers him a fist bump . By the end of the episode, he has the same fist elevated in a sling after struggling to keep his fist up throughout the episode . In "Lucky Penny", when the others do not believe that he can run the New York City Marathon the next day without training, Barney immediately agrees to do so . Although he succeeds, he is unable to walk afterwards . Although he thinks of himself as worldly, Barney is sometimes extremely naive, believing many lies his mother told him well into adulthood, such as believing that Bob Barker is his father . </P>

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