Jenny

Jenny is the wielder of lightning and a main character in the series.

Spirits 0
In the childhood spin-off, Jenny has long black hair with evenly-cut bangs across her forehead. She has her red and blue eyes from Spirits 2. She wears a white dress with black stockings.

Spirits 1
Jenny has short black hair and brown eyes in Spirits. She wears a white shirt with a purple collar and black pants with white shoes.

Spirits 2
In Spirits 2, she has long hair, red and blue eyes, and wears a white jacket and black pants. When she uses Mystletainn, her eyes are purple.

Spirits 3
In Spirits 3, her hair is still long, and her eyes change between red and blue, and purple. She wears the same white jacket, but now wears a black dress with black socks. At the end of the series, she wears the same scarf that King wears.

History
Jenny grew up in a small orphanage along with a handful of other children, one of whom was her closest friend. The two spent most of their time together until her friend passed away from the disease that swept through the small town. After that, she makes a contract with Or and is taken to the Temple of Spirits. It is later revealed that her friend was Leia, and the plague was a test created by a small group of Maya's worshippers, which was used to turn people into shadowy monsters and ultimately, feed the Falling Star.

Spirits - Twilight Arc
Jenny is sent to live on Earth again after spending her days with the spirits in the Temple of Spirits. Though she has difficulty getting along with people her age, Or follows her and teaches her how to interact with people. As a spirit, Or is invisible to the naked eye, allowing him to navigate the world with ease. However, this creates a bit of a problem as Jenny can see and talk to him normally while looking like she is talking to herself to normal people.

Eventually, she meets Johnny and Janelia, two people who she eventually trusts and becomes good friends with. She then finds out that they both have spirits with them - the spirit of light and the spirit of air. They defend the city from shadows, while meeting other spirit wielders along the way.

One night, they come into contact with Mystletainn, the cursed sword. They manage to defeat its wielder, a classmate, and shatter the sword. The fragments of the sword are blown by an explosion into different directions. Or requests that the Spirit wielders track it down, and while they do so, they come into contact with Twilight.

Jenny becomes friends with Kaido, but then is quickly betrayed by him as he tries to steal the spirits' powers to reconstruct Mystletainn. The Spirit wielders defeat him, but Jenny forgives him after Or lectures her not to hold grudges against people. This proves beneficial as Kaido tells them about Twilight's plan to obtain Mystletainn's power. Soon after Kaido joins them, he is attacked by Henry, who is revealed to have been in Twilight all along. Henry fails to kill Kaido when Jenny intervenes, but he makes off with the Mystletainn fragments.

They track Twilight down in their underground hideout, where they waged a battle that lasted through the night. At last, the Spirit wielders emerged victorious thanks to their combined powers. Unfortunately, Edison's ultimate plan was not to reconstruct Mystletainn, but to use its powers to open the portal for Maya - who was sealed away after a confrontation with Or - to return.

Spirits 2 - Lighthalzen Arc
When the remaining members of Twilight form an alliance with the Spirit wielders, Jenny wholeheartedly disagrees with the decision and wanders off on her own. She meets Richie again, who had been traveling the world as a photographer, and the two talk about their lives over the past few years. Richie gives her a picture he took while he was hiking, and they part ways. Or suggests that Jenny try to work with the others against their common enemy, Maya, and reluctantly, she agrees, heading back home.

Once reunited, the group form a plan to visit the floating city in the sky, Lighthalzen, in search of Mystletainn. Jenny meets Kenny, the president's son, and his three confidants: Vanessa, Will, and Thomas. The four reveal that the president and a mysterious figure have been planning to raid the city below and put a stop to the plague that's been spreading around the area. Jenny gets separated from Johnny, Janelia, and Edison, and ends up wandering the city with the four Lighthalzen citizens until she is confronted by Kaido, who is slowly turning into a shadow.

Or urges Jenny to fight and save Kaido from becoming one with the Falling Star, a huge mass of shadows that will consume the world if it becomes too powerful. Hesitantly, she fights him, but without the will to defeat him, can't win. Eventually, Kaido manages to gain some self-control, telling them that Ken was manipulating the president and that he now posesses Mystletainn. Kaido admits that he was always plagued and destined to become a shadow, and asks that he be freed before he is absorbed by the Falling Star. Reluctantly, Jenny ends his life, with Or reassuring her that this was what Kaido wanted.

Jenny and the others attempt to stop the president from launching the raid, only to find out that he was killed by Ken. As the battle between Ken, Edison, and Johnny come to an end, the city begins to fall as the core holding the island up starts to break. They try to evacuate people, but there is nowhere to go. They eventually meet up with Edison and Johnny, who have recovered Mystletainn. Galileo, the spirit of time, appears before them and makes a contract with Edison, who manages to heal the core and prevent it from falling.

Afterwards, Kenny takes over as president and orders their military to fall back. He promises to rebuild the city and return it to the way it was. The Spirit wielders return to their town with Mystletainn in tow.

Maya attacks the group as they arrive in the city, easily defeating them all. Before she is able to take both Edison and Mystletainn, Jenny grabs Mystletainn despite Or's warnings and realizes that Mystletainn is a Great Spirit just like Or - Mystletainn being the Spirit of Void. She is temporarily taken over by Mystletainn while she struggles to make a contract with him. Eventually, Or is able to interfere and force the contract to work out. With two Great Spirits on her side, Jenny drives Maya away.

Spirits 3 - Hero Arc
The Spirit wielders make their way back to their homes only to reunite again later in the old Twilight base. There, Or tells them that Maya plans to awaken the Falling Star and unleash it on the planet. The reason for this being that the spirits and heroes have gathered in one place - there is no better time than now to dispose of them all. He then goes to explain that he, Galileo, and Mystletainn were the Great Spirits who stood beside the five heroes who defeated the Falling Star once before in the past. Cake, who made a contract with one of the heroes, was not a Great Spirit, though she was a candidate for one. After this conversation, Jenny returns to the Temple of Spirits with Edison, where Galileo reveals that Jenny is one of the heroes reincarnated in this world. Leia, Kaido, and Maya were the other heroes, along with one more person. The heroes were special because they contained a fragment of the Spirit Soul, a flower-shaped gem that granted them a power to withstand the Falling Star even after it had consumed the world around it. The Spirit Soul allowed its user to be fully compatible with all spirits, with or without a contract.

Maya releases her last plague over the entire continent as the Spirit wielders race to stop her. Within the heart of the city, Maya and Jenny fight each other. Maya, unable to gain an advantage over Jenny, retreats and attemps to release the Falling Star using Edison, who had been involuntarily absorbing the shadows from all over the continent. Edison begins to turn into a shadow, causing the whole area to turn into a dark, dangerous place. Johnny and the other Spirit wielders are forced to retreat as the entire city becomes covered in darkness.

Leaving the rest of the shadows to the other wielders, Johnny and Jenny decide to fight the Falling Star directly. The two have trouble getting close with Maya defending the monster until Jenny's Spirit Soul awakens. It is revealed she and King are the same person, and King seemingly takes over control and fights off Maya with ease. The Falling Star goes out of control, killing Maya in one swift blow, and then proceeding to finish off King and Johnny. However, King manages to fend off the Falling Star and asks Johnny to retreat for the time being.

Jenny manages to gain control over her body again, and finds she is able to communicate with King, who appears in an ethereal form beside her. The two work together to fight off the Falling Star and King's power begins to manifest more and more, until the two are able to pierce right through the monstrous shadow.

In the aftermath of its destruction, Jenny and King appear in a different world, where they find Edison sleeping peacefully. Jenny, having gained King's full memories and his original mission, shatter this dream-like world and Edison wakes up, only to witness Jenny (not being able to see King) disappearing along with the rest of the shadows.

Spirits 4 - Soul Arc
Jenny finds herself in the world of shadows, where everything is dark and dreary. Jenny and King wander around the other world until they meet with a dark-haired boy, who they eventually find out is Edidon, king of this shadowy world which he calls "Second Earth". They don't get along at first - King and Edidon immediately start battling it out until Jenny calls a truce between them.

They find out Edidon is the true Falling Star who King fought a hundred years ago, but he lost the power to travel to the real world and so he's been stuck in Second Earth. He wants his revenge on Maya, but to his disappointment, Maya is already dead. Edidon then says the Eye of Abyss belongs to him, much to Jenny and King's surprise. It's revealed that Maya had taken his eye and given it to Edison.

While in the Second Earth, they discover the existence of The Link, a gigantic, monstrous being who's sole mission is to merge the two worlds together.

Lightning

 * Or's power allows Jenny to create a large two-handed sword that can emit electricity, thereby slightly increasing its range. When Jenny wields it, she can build up electricity and release it from any part of her body, as seen in Spirits when she defeated Henry with this method. When using his power to full extent, her eyes become blue and red, and she gets bright yellow lightning-like wings.

Void

 * Mystletainn's power allows Jenny to create a black longsword that emits dark energy. This weapon, although a sword, is very strong in ranged magic attacks. When waving the sword, it can create dark energy that splits and quickly travels in random directions. When using this power, Jenny's eyes become a bright purple color and obtains black, metal-like wings. Upon activation, the ground around her also cracks in random directions similar to her ranged attack.