[[WMG:XJ-9/Jenny Wakeman]]
->Voiced by: JaniceKawaye

The main protagonist and the "16-year-old robot" to which the title refers, a state-of-the-art sentient gynoid automaton created by Dr. Noreen Wakeman five years prior to the series, though she was designed as a 16-year-old girl. Though XJ-9 was designed to be Earth's protector, armed to the teeth with a wide range of weapons, devices, and transformations, she desires to live the life of a normal teenager and often makes this desire quite apparent to her friends and creator.

* ActionGirl
* AllOfTheOtherReindeer
* AmazonianBeauty: Though you can't tell from the character designs, XJ-9 is 6 feet tall, according to Professor Wakeman's specs.
* BadassAdorable
* BareYourMidriff: Her chassis design is meant to mimic this, complete with a large exposed screw for a "belly button".
* BewareTheNiceOnes
* BrattyTeenageDaughter: To Nora sometimes.
* CoolLoser
* CuteBruiser
* DoAnythingRobot
* [[DoesNotKnowHisOwnStrength Does Not Know Her Own Strength]]
* FemBot
* GenkiGirl
* GirlishPigtails
* {{The Hero}}ine
* IJustWantToBeNormal: Combined with IJustWantToHaveFriends: Being a superpowered robot wouldn't be so hard for her if there were more bots as advanced as her.
* JerkWithAHeartOfGold[=/=]NiceGirl: She often shifts between these depending on the episode.
* MagicSkirt: Justified, that skirt's made out of metal.
* PinocchioSyndrome: Averted - she's perfectly fine with being a robot, but wants acceptance and assimilation... which sometimes means playing the trope straight.
* PowerGivesYouWings: {{Jetpack}} wings to be exact.
* RedHeadedHeroine: Once had red body paint, and her makeshift human form is a redhead.
* RidiculouslyHumanRobot
* RobotGirl
* SuperStrength: "The strength of a million-and-seventy men," if the theme song is to be taken literally.
* [[SurprisinglyGoodEnglish Surprisingly Good Japanese]]: Helped by the fact that her VA JaniceKawaye is also Japanese.
* TelescopingRobot
* WakeUpGoToSchoolSaveTheWorld
* YoungerThanSheLooks: Technically has been alive for about 5 years, but has all the mentality of a teenage girl... usually.
** However the fact that Jenny being physically five years old, has had a drawback of being forced to be in Kindergarden for the majority of the episode "I was a Preschool Dropout".
* YouGottaHaveBlueHair

[[WMG:Brad]]
->Voiced by: Chad Doreck

Jenny's best friend and next-door neighbor.

* CasanovaWannabe
* CoolLoser
* CrouchingMoronHiddenBadass: His over-enthusiasm for trying to be a hero can be more trouble than help, but when he gets serious he can be pretty significant help.
* DistressedDude
* IJustWantToBeSpecial: To contrast him with Jenny's desire to be a normal teenager.
* NiceGuy
* PluckyComicRelief
* RedHeadedHero

[[WMG:Tuck]]
->Voiced by: Audrey Wasilewski, Jess Harnell

Brad's little brother.

* AnnoyingYoungerSibling
* BadassAdorable
* DistressedDude
* {{Gasshole}}
* {{Keet}}
* KidAppealCharacter
* LargeHam
* OnlyOneName
* WholesomeCrossdresser:
-->'''Tuck:''' What? Can't a guy wear pearls and taffeta around here?
-->'''Nora:''' Strictly speaking, only after 6.

[[WMG:Nora Wakeman]]
->Voiced by: CandiMilo

An elderly spinster robotics scientist and the one who built XJ robots, who is often simply refers to as "Mother" or "Mom" by Jenny and her sisters.

* AmazinglyEmbarrassingParents: On occasion.
* CoolOldLady
* GadgeteerGenius
* MadScientist: One of the saner ones.
* MamaBear
* MeddlingParents
* MotherlyScientist
* NeverMessWithGranny: She used to be part of the skyway patrol prior to the series.
* ParentalObliviousness
* TheProfessor
* SiblingYinYang: With Wisteria, science VS nature.
* TrulySingleParent

[[WMG:Sheldon/Silver Shell]]
->Voiced by: QuintonFlynn

Jenny's self-proclaimed romantic admirer.

* AsianAndNerdy: He's apparently half Asian.
* CrouchingMoronHiddenBadass: He was a space pirate [[spoiler:''for decades'']]. And a secret agent.
* DistressedDude
* DoggedNiceGuy
* DudeWheresMyRespect: It's not that he can't ever get any respect, but he has to work ''much'' harder for it.
* GadgeteerGenius
* HeroWorshipper: A variant in that he's smitten with XJ-9 as well as seeing her as a role model.
* LargeHam: As the Silver Shell.
* OlderThanHeLooks[=/=]ReallySevenHundredYearsOld: [[spoiler: After the episode "Good Old Sheldon" he's only physically 15, but now officially 105 years old. Holy cow.]]
* PostKissCatatonia: In the Christmas episode, Jenny gives him a peck on the cheek and he is frozen in position then slowly and rigidly tumbles down the stairs.
* RescueRomance: Sheldon meets and falls hard for Jenny after she saves him from some bullies in shop class.
* {{Robosexual}}
* SingleTargetSexuality: Jenny-sexual.
* StalkerWithACrush
* TookALevelInBadass: In "Agent Double-O Sheldon".

[[WMG:Jenny's "sisters" XJ-1 through XJ-8]]
->Voiced by: JaniceKawaye (XJ-1), KathSoucie (XJ-2, XJ-3, XJ-4 and XJ-5), CandiMilo (XJ-6), Audrey Wasilewski (XJ-7 and XJ-8)

XJ-9's prototypes and "sisters".

* BabyLanguage: XJ-1.
* [[BigLittleBrother Big Little Sister]]: XJ-8.
* BreakOutTheMuseumPiece[=/=]MisfitMobilizationMoment: Once, after Jenny got captured by the Cluster. With the exception of XJ-8 they don't appear to be combat-ready, but do okay as they apparently have the same [[TelescopingRobot telescoping armor]] Jenny does.
* CrossdressingVoices: XJ-8.
* CuteClumsyGirl: XJ-3.
* CyberCyclops: XJ-3 and XJ-6.
* TheEeyore: XJ-7.
* FlawedPrototype: All of them. Unlike most examples of the trope, though, they are clearly functional testbeds that do well within the parameters of their design.
* FrickinLaserBeams: XJ-2.
* HiccupHijinks: XJ-2 again.
* MoodSwinger: XJ-6.
* MotorMouth: XJ-5.
* NeatFreak: XJ-4.
* RidiculouslyHumanRobots: The XJ sisters appear to be gradually working towards this. May also be why XJ-8 isn't the last in the line.
* SuperPrototype: XJ-8 is physically stronger than Jenny - to the point that she's really not looking forward to fighting her - but doesn't have Jenny's "quirk and charm" according to Dr. Wakeman.

[[WMG:Queen Vexus]]
->Voiced by: Eartha Kitt

* ArchEnemy
* BigBad
* {{Determinator}}: Even after losing multiple times to Jenny [[spoiler:even to the point of losing her status as Queen]], she still insists on attacking Jenny any chance she gets.
* EvilMatriarch: Subverted. She may be evil and the BigBad of the show, but she still loves Vega (almost to the point of being [[MyBelovedSmother overprotective]], even.)
* GodSaveUsFromTheQueen
* HellishPupils
* IneffectualSympatheticVillain: Starts off as a huge threat, but becomes an easily dispatched threat later on. This really gets hammered home, though, when [[spoiler: she eventually loses her dictatorship over Cluster Prime]].
* TotallyRadical: She would have blended in while she was destroying Jenny if she only realized that TheRoaringTwenties was over for almost a century now.
* TsurimeEyes

[[WMG:Kilgore]]
->Voiced by: TaraStrong

* Catchphrase: '''Surrender'''
* DeathbringerTheAdorable
* {{Determinator}}
* EnemyMine: With Jenny in "Enclosure of Doom".
* EvilSoundsDeep: Spoofed in the first few seconds of the episode he's introduced, as he's not wound up yet.
* HarmlessVillain
* IneffectualSympatheticVillain
* TheNapoleon: If it's 10 1/2 inch stature has any indication.
* OnlyOneName
* OutGambitted: In "Enclosure of Doom"
* ScareChord: Spoofed in "Enclosure of Doom".
* SayingSoundEffectsOutLoud
* ThirdPersonPerson
* VillainWithGoodPublicity: Sure it may be threatening, but what part of "Villian" dont they (Refering to the people who take a liking to it) understand?[[hottip:*:All of it apperently.]]
* WindUpKey: It's Powered by Watch Spring and a wind-up key.

[[WMG:Vega]]
->Voiced by: ThoraBirch

* BladeBelowTheShoulder
* {{Expy}}: In universe, she's this for Jenny among her circle of friends, who, incidentally, [[YouAllLookFamiliar look just like Jenny's friends back home]].
* PowerGivesYouWings: Dragonfly wings, in her case.

[[WMG:Misty]]
->Voiced by: Audrey Wasilewski

* PunchClockHero: In "Mist Opportunities".
* [[EvenEvilHasStandards Even Mercs Have Standards]]: Even though she only does hero work for money and sees no problem with meditating while a KillerRabbit destroys the town, she was clearly disgusted that her former teammates lazed around and actually bet against Jenny as she fought against a [[ItMakesSenseInContext Giant Monstrous Frog]].
* [[EvilCannotComprehendGood Mercenaries Can't Comprehend Heroics]]: She was absolutely confused by Jenny's remorse for [[SympathyfortheDevil scaring the Krust Cousins to tears]].
* EvilFormerFriend: She was pretty much Jenny's best female friend. But Misty got more ruthless to the point she only thought of helping people if she could benefit from it. All to the point where Misty nearly kills Jenny in a fight where Jenny [[CurbStompBattle was clearly outmatched]]. The only thing that stopped Misty and snapped her somewhat back was Jenny [[TearJerker still pleading that she still saw her as a friend]].
* MoralityChain: Arguably Jenny.
* SuperpowerLottery: Let's see: she's a skilled [[SupernaturalMartialArts martial artist]], has SuperStrength, can [[FlyingBrick fly]], turn into [[SuperSmoke mist]], shoot [[EyeBeams laser beams from her eyes]], and [[MindManipulation control peoples' minds]].
* SuperSmoke: Her most often used superpower is her ability to turn into a cloud of purple mist at will (hence her name).