|Hair color||Purple (dyed)|
|Relationship|| Richard Gooberman (unseen, broken up)|
Jonesy Garcia (broken up)
Hunter (broken up)
Stone (broken up)
|Nicknames|| Nose Ring (Ron)|
Nikster (The Clones)
Nikkikins (The Clones)
Nik-a-rama-ding-dong (The Clones)
The Grinch (The Clones)
|First Appearance||Take This Job and Squeeze It|
|Last Appearance||Bye Bye Nikki? Part 2|
|Voiced by||Stacey DePass|
Nikki's first appearance comes in "Take This Job and Squeeze It," where while walking with Jonesy she pokes fun at his over-the-top ideas of what having a summer job will be like. The personality that she gives off during this walk holds strong throughout the show, as Nikki is constantly depicted as an irreverent and snarky teenage girl. She is one of the original five members of the group, and takes the longest amount of time to warm up to Caitlin.
Nikki works at the Khaki Barn, a retail establishment which she absolutely loathes due to its commitment to conformity. She works there because it was one of the only stores that was both hiring and willing to take her on as an employee. Her inability to be hired elsewhere was seen in "Welcome to the Darth Side," where she was unable to procure employment anywhere besides Stereo Shack–and even then only because Darth had a crush on her. While working at the Khaki Barn, Nikki is often lazy and surly and is generally regarded as one of the worst employees there; in fact, in "Employee of the Month," she somehow managed to have -5% sales over the course of a week. Despite this, she has shown an ability to sell clothes (especially to Kyle Donaldson) when she puts her mind to it; she did so in "The Sushi Connection" and "Oops, I Dialed It Again." Nikki's attitude is also somewhat appreciated by her coworkers, who like that she leaves all of the commissions to them.
This doesn't stop the Clones from frequently getting on Nikki's nerves. Often, it seems to be their personality that irritates her, as they act as ditzy, Khaki Barn obsessed airheads much of the time; however, they have occasionally shown impetus for Nikki's reaction. For example, in "The Wedding Destroyers" they decide that Nikki shoplifted goods from the store with no evidence whatsoever, and in "Another Day at the Office" they use her as the "fashionably-impaired girl" in a magazine ad. Despite this, it is uncertain whether their actions are done out of malice towards Nikki, out of a lack of empathy for her, or whether they are a reaction to Nikki's often snooty attitude towards them.
In addition to being snarky and sarcastic, Nikki is not much of a romantic. In part, this is attributable to bad experiences in the past: in "Stupid Over Cupid," it was mentioned that Nikki had once had a prankster paste her face all over naked Cupids put up in the school, and that she once got food poisoning at a Valentine's Day dance from eating year-old chocolate creams given to her by her date. Also, over the course of the show, despite only being involved with three people romantically she was treated poorly by two of them. The first, Hunter, cheated on her with Caitlin and several other girls; the second, Stone, ended up breaking up with her in order to get back together with his ex (and tried to hire Jonesy to do it for him).
However, Nikki has the longest-running relationship in the show of any of the leads. Her (second) relationship with Jonesy lasted through the second half of the series run and was mostly problem-free, with exceptions occurring in "Silent Butt Deadly" and "Insert Name Here." Jonesy and her fit well together, as they know a lot about each other and each other's personalities, and are able to understand each other well and support each other while staying friends and often making fun of each other. In fact, their first attempt at a relationship only failed because Nikki was afraid that the relationship was becoming more important than their friendship–a pitfall that they ended up avoiding after getting back together again.
Despite her sarcastic and often aloof manner, Nikki has been shown to care for her friends deeply. This is best exemplified in "Bye Bye Nikki? Part 2," where she shows how much she cares for her friends by giving them all very personal going-away gifts: to Caitlin she gives Caitlin's original cut-up credit card so that Caitlin will know that she can survive anything, to Jen she gives a flier for Jen's first snowboarding competition, and to Jude she gives a silly hat that works well with his quirky personality. The only people who don't receive "gifts" per se are Wyatt and Jonesy; Wyatt is shown a copy of the first demo album he ever recorded and Nikki tells him that she still listens to it, while she tells Jonesy that she'll always love him.
- Nikki finds her parents embarrassing as they wear clothes from the 1970s.
- Nikki's true hair color is most likely black, or a dark purple, similar to Jonesy's dark blue, as revealed by a picture from first grade in "Breaking Up with the Boss' Son".
- Nikki enjoys listening to metal and punk, is a fan of a band called the Mighty Weasels, and secretly loves DawgToy, a popular boy band.
- Nikki is the shortest of the friends.
- Nikki is a Pisces, according to "Idol Time at the Mall", meaning her birthday is sometime between February 19 and March 20.
- Nikki is of Chinese descent, although her phone has a Japanese Flag design on it (although she might be of both Chinese and Japanese descent).
- Nikki loves the smell of newborn babies, as shown in "Labour Day - Part 2."
- Nikki is the only female in the group who has been fired, and also the only female who hasn't worked at the Big Squeeze.
- Nikki has known Jen and the boys since they were in kindergarten.
- Nikki sports a nose ring, a ring on her left eyebrow and four piercings on both of her ears.
- Nikki and Wyatt have been shown to enjoy debating each other's preferred musical tastes, which she once used this to coerce Wyatt into climbing down a ladder that Jude had convinced him to climb, despite his fear of heights.
- Nikki claims that she will not be working at a mall in five years in "Take This Job and Squeeze It."
- She also has stated that she does not want to be working for the Khaki Barn in 2 years.
- She once tried to get a job at the Galleria Mall travel agency, but failed due to a bad interview.
- It is revealed in "6teen: Dude of the Living Dead" that Nikki has a sister, though this might not be true since it was a dream that Jude had. However, in "The Fake Date," she tells Jonesy that she has a 6-year-old nephew, which indicates that she has an older brother or sister.
- Assuming that Nikki does have a sibling or siblings, she, Jen and Jonesy are the only three with known siblings (with Jen and Jonesy also being stepsiblings).
- Caitlin is the only one of the main six confirmed to be an only child while it is never said whether Jude or Wyatt have siblings (the latter has mentioned that he comes from a big family, so he might have siblings).
- Nikki is the only member of the gang to have both (biological) parents appear; the parents of Caitlin, Jude, and Wyatt have never appeared, and neither Jonesy's mother nor Jen's father has appeared in the show.
- Nikki is more emotional during her menstrual cycle.
- Normally, Nikki hates chocolate, but during her menstrual cycle she eats chocolate and in "Stupid Over Cupid" she is seen eating chocolate ice cream.
- Nikki loves to eat popcorn with green gummy bears on top.
- Apparently, Nikki has a sweet tooth, because when Caitlin gave the gang a cake for a "lame anniversary" (according to Nikki), she was quite eager to have a slice of it.
- Nikki used to do dance and wore glasses in the first grade.
- Nikki hates makeovers and girly girl things. Unlike Caitlin and Jen, Nikki prefers a backpack to a purse and is the only girl in the group to not wear a skirt.
- It is revealed in "J is For Genius" that Nikki is in the top 5 IQ percentile.
- This equates to an IQ of 124 or higher.