When the writing team of Kevin Eastman, Bobby Curnow, and Tom Waltz first envisioned Jennika it's unlikely they foresaw the impact that the former Foot Clan assassin would have on the Teenage Mutant Ninja Turtles franchise. While technically the first, April O'Neil's brief transformation in Archie Comics' Teenage Mutant Ninja Turtles Adventures Winter 1994 Special doesn't really count (she wasn't even a Turtle for the entire issue) and Venus de Milo only ever appeared on the show Ninja Turtles: The Next Mutation, making Jennika the first female Ninja Turtle to regularly appear in any of the major comics continuities.

In the almost 40-year history of Teenage Mutant Ninja Turtles comics, Jennika represents a real change for the franchise. Before IDW got the rights to make TMNT comics, a female turtle would never have been possible. Peter Laird, TMNT co-creator, has been notorious for his hate of Venus de Milo and has spoken out strongly against adding an additional turtle if it's just going to be a boring carbon copy of the same. Thankfully Jenny is no copy. She's been popular enough in the current run to get not one but two solo mini-series. But there's a lot more to know about the newest addition to the Ninja Turtles.

Jennika's first appearance was in IDW's Teenage Mutant Ninja Turtles #51, written by Eastman, Curnow, and Waltz, and illustrated by Ken Garing. She was still human then, a member of the Foot Clan who didn't like the non-violent policies that Splinter was forcing on the ninjas. She joined with the Street Phantoms and attempted to assassinate Splinter. Soundly defeated and placed under the tutelage of Leonardo, Jenny began to respect her new family, saving Splinter's life and taking on a larger role beside the Turtles.

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After the Turtles had a dispute with Splinter and left the Foot Clan, Jenny became Splinter's second-in-command for the Triceraton invasion and stepped up as caretaker to the orphans the Turtles rescued from the Rat King. Throughout all this Jennika gained a new respect for Splinter and the Turtles.

The transformation happened in Teenage Mutant Ninja Turtles #95 written by Eastman, Curnow & Waltz with art by Dave Wachter. Stabbed by Oroku Karai for wanting to stand with her new family, Jennika was given an emergency blood transfusion from Leonardo. The mutagen and turtle DNA in Leo's blood bonded with Jennika and mutated her into a Mutant Ninja Turtle.

Before she was a member of the Foot Clan, Jenny grew up on the streets. She used alcohol and punk music as tools to escape an abusive home life. Silas, Jenny's on-again-off-again boyfriend, talked her into a store robbery that ended horribly after their accomplice shot a bystander. Jenny would take the fall and ended up in prison where she met a member of the Foot Clan. One prison escape later had Jennika seeking out and joining the Foot Clan.

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After Old Hob's mutagen bomb turned a portion of New York's population into mutant animals, Jennika, wearing a yellow bandana and using tekko kagi claws, became a protector of the newly dubbed Mutant Town as seen in Jennika and Jennika II written by Brahm Revel and Ronda Pattison and illustrated by Brahm Revel, Jodi Nishijima, and Megan Huang.

Jennika's role as protector, as well as her experiences with the orphans the Turtles saved, led to her adopting a young albino turtle child she found on the streets whom she named Lita after her favorite singer Lita Ford. All of that would be complicated by the appearance of a time-traveling Lita from the future.

Future Lita encouraged her adoptive mother to pursue one of her greatest dreams: to start a metal band. According to Lita, Jennika has to play music or she'll destroy the world. This angered Jennika who feels she has moved past the role of assassin. Fortunately, the disruptive appearance of Bebop and Rocksteady gave Jennika the perfect excuse to focus that anger, challenging the former musicians to a Battle of the Bands instead of a battle for the fate of Mutant Town. Jennika has since gone on to become an extremely popular addition to the Ninja Turtles, and a highly valued member of their team.

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