Her first appearance, alongside the other two Outcasts, was Outcast Times at A. Nigma High. Jenny Jergens plays a large role in the fourth season, where she and Tina often work together to aid Lee. Like Tina Kwee, Jenny has a crush on Lee Ping but eventually gets over it as seen in Mannifestum Rising.
Prior to Series start
Jenny was once a popular student in A.Nigma High, which is backed up by Lee when he spectulates that she might have been part of the brainwashing. Cam at one point says that "they used to be popular." She is also one of Lee's first friends when he was in grade 5 and was invited to his 10th birthday party. She has no memory of the event however, as she suffered amnesia in sixth grade after a horse kicked her in the head. Jenny is also the first person to be brainwashed before the events where Lee was accused of the prank.
Her mother is a musician in a band. She had a twin sister, Jenny's aunt, who was a scientist that mysteriously disappeared years ago. From a photo that Tina uncovered she appears to have been part of the original brainwashing team headed by General Barrage. Because of her knowledge of the subject, it may be possible that she was relocated to Coral Grove.
Jenny is, once again, not seen at the beginning of Season 2 until Lee reveals a picture of his 10th birthday party where Camillio was hypnotized. They speculate who brainwashed Cam as the only people who could know his trigger word, "butterscotch", were at the party. During the search for the Red Tatzelwurm's whisker, Cam questions Jenny about Lee's birthday party, and she reminds him that she suffered amnesia a year later and has no memory of the party or the trigger word.
In The Outcasts Strike Back it is revealed that the Outcasts accidentally destroyed the Tatzelwurm whisker Lee gave them and then secretly dug their way into the underground tunnels to find a new one. Jenny steals Lee's backpack and the Key inside it to help them search. When Lee finds them she reveals that she also found a library book that she believes contains information on the Tatzelwurm and how to use it's whisker. When Barrage finds out she stole Lee's backpack he sentences her to a week of detention. Jenny decides to use the time to work with Lee in studying the book and helping him unravel the conspiracy behind the pyramid, even joining him on his covert missions to spy on the council and track down Finnwich. Jenny is also seen in the intro waving to Lee.
At the start of season 4 Jenny continues to study the book with Tina's help. Now able to read the Arcanum Manifestum thanks to Finnwich's Quadocle the two make great progress in unraveling the secrets of Coral Grove, and they grow close as friends. However she tries to prevent Lee and Tina from spending time together. She later convinces Tina to make a pact that neither will pursue Lee in order to preserve their friendship. In "Splitting Hairs" Jenny accepted a ride to school from the Serpent, not realizing he was using her to infect the school with lice. She quickly became infatuated with him, and despite Tina warning her not to trust him, she continued to see him even after he took her deep into the woods and left her in the rain in "Revenge Of The Cycle Killers", oblivious to the fact that he was Lee's rival. In "Serpent Strike" Jenny finally sees the Serpent's true colors when he takes her on a picnic only to steal the Book from her.
Later on in the episode Game of Clones, Jenny tried to look for Tina and was suddenly ambushed by Principal Wurst, who then takes her to the principal's office. To Jenny's astonishment, within the office is another principal Wurst. They interrogated her about the whereabouts of Finnwich's Book. However, since Jenny refused to answer the question, Wurst then told her that she will be sent to Coral Grove along with Tina so they can continue the interrogation there. Jenny is put in in the same truck as Tina where Tina apologises to Jenny for not warning her about it in the first place.
Ultimately both of them are sent to Coral grove as they know too much about the Pyramid, the Conspiracy and Coral Grove. She and Tina eventually arrive at Coral Grove where they were interrogated by the Wurst clones about the Book containing information about the Pyramid and Finnwich's cipher, but since both Tina and Jenny did not give the proper information the Council needed, they were imprisoned.
Jenny, along with Tina, was eventually rescued by Lee, Holger and Biffy. After escaping the facility and promptly returning due to Lynch Webber, they reluctantly allow Lynch to lead them to Finnwich. The group split up, with Tina making sure that Lynch doesn't get them caught, Holger and Biffy trail the latter's parents, and Jenny and Lee check out the clone storage area for Mrs.Ping. Jenny then asks Lee if they only came for Tina, but Lee replies that they came for both of them. Jenny then reveals that she messed up Lee's chances with Tina due to their pact to not date Lee. Afterwards, she tells Tina that the pact they made was off, due to her realising that Lee and Tina liked each other.
Her sudden fall from popularity to social pariah due to her hypnotically induced nose-picking habit appears to have made Jenny misanthropic and mistrustful of people. She steals Lee's key instead of asking for it because she assumes that he would refuse to help the Outcasts again. Even when she starts working with him she is sarcastic and snarky to Lee's other allies and especially hostile towards Tina, due to feelings of rivalry. Jenny was clearly touched by Lee's decision to help her and the other Outcasts even after she had stolen his backpack, as evidenced by her decision to stay and help Lee fend off the Blue Tatzelwurms while Lou and Deuce were willing to leave him and run. She seems to have developed feelings for Lee and is not shy about calling him up on video chat.
Her antisocial nature may also be due to her dislike of seeing people's look of disgust at her nose-picking which she constantly tells them is a curse that she is unable to control despite her best efforts. On missions Jenny has shown herself to be bold and brash, jumping at the chance to take risks and refusing to be left out. She was also very willing to get revenge on Lynch for kidnapping her and Tina by punching him with boxing gloves Tina gave her. Her fearless nature suggests that because of her outcast status Jenny feels she has nothing to lose. While initially snarky and defensive towards Tina she was begrudgingly accepting of her help in studying the book and over time warmed to her as a research partner and later a friend. Although even then Jenny sought to compete with her for Lee's affections, which suggests a somewhat ruthless attitude. However she does have a regretful side as shown when she apologised to Lee privately for mucking up his chances with Tina and will do whatever it takes to fix it.
As a detective Jenny is very diligent and observant. While studying the book she noticed the library card was missing, which was how Lee and Co. were able to find out about Niles Peg. She is also quick-witted and not above using her 'curse' to her advantage. In Pyramid Scheme she was able to get Lee out of class by telling Mr. Langhorne that a blank paper was a note from the principal. Since Jenny offered it to him with her nose-picking hand he decided not to read the note himself and just took her word for it. She later tried to manipulate Tina into leaving her alone with Lee by using her known dislike for Chaz. Though unsuccessful in that instance Jenny seems to have a knack for social engineering.
Her infatuation with the serpent shows that Jenny will forsake her better judgement in the prescence of a pretty face. It further suggests that beyond her sarcastic surface there is a part of her despartely seeking acceptance. Like the other Outcasts she wants to reclaim her popular status.
- "Gee Inspector Obvious, what gave it away, me holding the book or me walking to the library?" - "Fight or Flight"
- "What, work together? Heck, maybe you're right. We could be Bonnie and Betty Brave, detective sisters in The Case of the Would You Get Off My Back and Go Away Already?!?" - "Fight or Flight"
- "Ever heard of a little something called personal space?" - "Fight or Flight"
- "But the boogers help the pages stick!" - "Fight or Flight"