Series creators Ryan Murphy, Brad Falchuk and Ian Brennan initially conceived of him as a fashionable gay countertenor who is routinely bullied at school.
His storylines in the first season focus on his struggle with his sexuality as he comes out to his father and friends, and deals with his romantic feelings for Finn Hudson, the straight co-captain of the glee club.
In the show's second season, Kurt is forced to transfer to a private school for his own safety after a closeted gay classmate bullies him relentlessly and then threatens to kill him.
Kurt joins the Dalton Academy Warblers, the school's glee club, which is a competition rival of New Directions, and is befriended by their openly gay lead singer Blaine Anderson.
For the remainder of the series, Glee charts Kurt's life in Lima and New York as he grapples with young adulthood and realizing his career ambitions.
[20] Kurt competes against the glee club's star singer Rachel Berry (Lea Michele) for a solo on "Defying Gravity" from the musical Wicked.
However, after Burt receives a phone call labeling his son "a fag", Kurt intentionally misses the song's high note in order to lose the competition and save his father from further harassment.
[23] In "The Power of Madonna", Kurt and Mercedes, dissatisfied with their limited solo opportunities within the glee club, become singers for the school's cheerleading squad, the Cheerios.
[25] Kurt, who becomes jealous over their growing relationship, briefly attempts to reclaim his father's attention by acting more masculine: he imitates Burt's style of dress, asks him for advice on performing songs by his favorite artist, John Mellencamp, and arranges to have Burt walk in on him kissing cheerleader and glee club member Brittany Pierce (Heather Morris).
[30][31] In "Never Been Kissed", Kurt goes to spy on the Dalton Academy glee club, the Warblers—New Directions' primary competition for Sectionals—and meets openly gay student Blaine Anderson (Darren Criss), who then flirts with him while singing lead in a Warblers performance of "Teenage Dream".
Burt and Carole get married, but when Karofsky's expulsion is reversed by the school board, the newlyweds decide to spend the money they had saved for their honeymoon on tuition to transfer Kurt to Dalton Academy, which enforces a zero-tolerance policy against bullying.
[45] Kurt tries out for the musical, but the directors aren't convinced that he's masculine enough to portray Tony, the romantic male lead, and cast Blaine instead, even though he's only a junior.
Kurt applies for a job at Vogue.com and his editor, Isabelle Wright, who is also from Ohio, hires him partially based upon his portfolio of outfits and is impressed with his intuition and style.
Kurt continues working at Vogue throughout the season, and Isabelle encourages him to try to forgive Blaine, and at Thanksgiving, she brings her friends over to their loft and throws him a "kiki."
When Kurt reauditions for NYADA, he is initially rejected, because Carmen Tibideaux sees his technical skill and tells him that he can sell a number, but doesn't believe that he is emotional enough to be an artist.
Though he initially panics, Rachel convinces him that he doesn't need his bells and whistles to perform, and he chooses to sing "Being Alive" from Company, which impresses the NYADA audience, and he later gets a letter telling him that he has gotten in.
Glee's costume designer Lou Eyrich said in an interview with the Seattle Times that Kurt is one of her favorite characters to dress: "He never, ever repeats and you get to push yourself creatively.
"[59] Eyrich set out to dress Kurt with tailored pieces that "exude his quietly flashy dapper dandyism",[60] mindful that as the son of a car mechanic, "he doesn't have a lot of money".
The episode in which Burt defends his son against Finn's name-calling prompted a response from Eric Goldman of IGN, who declared it "one of the heaviest scenes Glee has ever delved into".
"[70] When imagining Blaine and Kurt's potential future together, Murphy expected to treat them the same as all other Glee relationships by making their pairing "as flawed and as exposed as everyone else's.
Murphy selected "Defying Gravity" for the episode after Colfer related a story in which his own high school drama teacher had refused him the opportunity to perform the song because it was written to be sung by a female singer.
[88] Entertainment Weekly's Sandra Gonzalez also praised the rendition: "Kurt apparently picked up a few helpful notes ... from his Warbler brothers and emerged an even better solo singer than I recall.
[91] Kurt has received mainly positive reviews from television critics, with many saying that Colfer's portrayal (along with Jane Lynch's performance as Sue Sylvester) stole the show from lead actress Lea Michele as Rachel Berry.
NPR's Linda Holmes found it "absurd" that a teenager as deeply in denial as Karofsky would transition from bullying to kissing Kurt so quickly and described it as "emotionally and behaviorally unsound".
[97] Leah Anthony Libresco of the Huffington Post called the episode "extraordinarily counterproductive", and disapproved of Will treating Kurt's upset as the key problem, rather than the unchecked bullying provoking it.
She found Blaine's advice to Kurt "misleading and dangerous", especially the suggestion that targeted children should be held responsible for confronting their attackers and putting themselves at risk of further injury, rather than for protecting themselves.
[98] Poniewozik noted that the storyline was inherently flawed, as the show had previously treated bullying in a light-hearted rather than serious manner, but said that its saving grace was the focus it placed on Colfer: "probably the strongest actor with the most interesting character among the Glee kids".
[99] The love story involving Kurt and Blaine was met with critical acclaim, especially the events in the "Original Song" episode where the characters first kissed.
[105] Crystal Bell of HuffPost TV was impressed by the way the characters' relationship "inspires gay youth in a way that we haven't seen on network television yet" and called them "amazing role models for all teens", and The Atlantic writer Kevin Fallon said it was "remarkable" and a "milestone" that "the decision by gay teen characters to lose their virginities is given equal weight to that of a straight couple".
[112] AfterElton.com said, "Colfer's portrayal of Kurt is that he's taken a character that's in many ways a gay stereotype ... and turned him into a well-rounded person who can both make us laugh and break our hearts.