On top of a building in Japan, the Kamen Riders of the Igarashi family are fighting Giff Juniors while trying to reach a device that is in the process of sapping away the Riders' powers to transform.

"We have to reach that device!" Live said, still fighting against the horde of Giff Juniors

"That's easier said than done, Daiji! Hehe, it's still fun to kick their asses!" Evil said as he punched one of the Giff Juniors, sending them flying towards Aguilera and Jeanne.

"Hey hey! Calm down, Kagerou." George Karizaki said as he attempted to shut the machine down.

"We have to buy Karizaki-san time to shut that thing down!" Jeanne said as she punched and kicked away some Giff Juniors.

George was close to shutting the device down but then someone from the shadows used a demon and knocked him away "No! I needed more time!" The machine goes off, indicated by a beep "Oh no. Goddamn!"

During the fight, the Kamen Riders transform into their civilian forms and the demons return to their hosts.

"It seems like you all can no longer transform." The mysterious person emerges from the shadows, revealing a man in a green suit.

"Ortega!" Hiromi shouts, Ortega looking at the former riders with an evil grin.

"Surprised? I used that device to stop all of you specifically. Which means you all can't transform into Kamen Riders to stop me or my Neo Deadmans." Ortega said as a Helicopter flew upward allowing him to step inside and fly to parts unknown.

One Year Later…

In a house in a town called Gravesfield in America, a Dominican-American girl, named Luz Noceda, hears her alarm clock go off and she sleepily tries to turn it off but gets out of bed anyway "Great… another school year." Luz said as she went over to her closet and grabbed her clothes for the day.

She looks into the mirror of her bathroom and fixes her pixie-cut hair before hopping into the shower. After the shower, Luz puts on her clothes for the day, which consists of a pair of ebony earrings, a short-sleeved half-white, and half-indigo hooded shirt with cat ears attached to the hood, high-waisted jean shorts, dark gray capri leggings, and a pair of white loafers.

The girl goes downstairs to see her mother, Camilla, making breakfast "Buenos Dias, Mija." Camilla said in Spanish.

"Buenos Dias, Mamí," Luz said as she grabbed a bowl, a carton of milk, and a box of cereal.

As Luz puts the cereal in the bowl and adds the milk to it, she sees a strange humanoid creature with hints of purple and shades of seafoam green, but it is tangible, almost see-through like a Ghost.

"I do believe you should eat a full balanced breakfast before attending school."

"I am eating my breakfast," Luz said to the creature, getting her mother's attention.

"Is that… 'ghostly creature' back?" Camilla asks.

"Yeah. I just hope I don't get in trouble because of it." Luz said with a frown, causing the creature to flinch, clearly hurt and offended by Luz's words.

"Trouble!? Me?! Bite your tongue! I am only looking out for you. Don't be ungrateful!" The creature yelled.

"Well, if it gets bad again…"

"I know, Mamí. I'll be sure to take the medication again." Luz said, pulling out a small bottle of pills.

"I do believe it is almost time for the bus to arrive. If you do not leave now, you'll be late for school."

Luz looks at the time and quickly gets out of her chair and grabs her backpack in a hurry when she sees the time "Aw crap! I'm gonna miss the bus!" Luz said.

"Wait! What about your lunch!?" Camilla asks.

"I'll eat something at school!" Luz yelled as she ran out of the house as fast as she could.

Luz was fortunate enough to catch the bus and get to school on time, now walking in the hallway of Gravesfield High towards her locker but that's when she sees a student that she didn't recognize.

The boy had fair skin, curly black hair, and brown eyes. He was wearing a black shirt with a jacket that looked like a lab coat, peach-colored shorts, and brown sneakers.

Luz took a closer look at him and realized that he was lost. She decided to walk up to him and help him out "Hi there!" Luz said with an energetic grin as the boy looked up from the paper and looked at Luz.

"Hah? Oh, Konichi- I mean, good morning. I'm sorry." The boy said.

"It's okay! Are you a new student?" Luz asks.

"Ah, Hai! I mean, yes." The boy said before blushing "Sorry, I used to go to a school in Japan, so my English is a little rusty. It's been a long time since I used to live in America."

"You lived in Japan!? That's so cool! I've always wanted to go there!" Luz said excitedly.

"I can see that. I've always loved being there." The boy said before Luz looked at the paper in his hands, remembering why she walked up to him.

"Oh, right. You're lost right?"

"Yes. I'm trying to find Morven-sensei's classroom." The boy said.

"Oh! That's my classroom! I can show you where it is!" Luz said as she and the boy headed over to the classroom.

The two enter the classroom, Luz takes her seat as the boy writes his name on the board just as the teacher walks in with a cup of coffee and his teaching materials "Um… what are you doing?" Mr. Morven asks.

"I was writing my name so I can introduce myself." The boy said.

"Ah, you're the new student then, correct?" Mr. Morven asks.

"Yes, Sensei!" The boy said as the school bell rang, signaling the students to take their seats.

"Okay, class! Today we have a new student joining us today. Go ahead and introduce yourself." Mr. Morven said to the boy.

"My name is Connor. Connor Karazaki! I hope we have an exciting and climactic school year together!" Connor said as he saw an empty seat right next to Luz "Sensei. May I sit next to her?" Connor asks as he points to the chair next to Luz.

"Sure." Mr. Morven said, nodding in approval as Connor went and took his seat next to Luz.

Luz gives him a friendly smile as the two turn their attention to Mr. Morven "Now before we begin today's lesson, we have a sudden morning assembly today." The students' groans echo all across the classroom as Connor is the only one to raise his hand in confusion "Yes, Connor?"

"What is the school assembly about?" Connor asks.

"I don't know. Principal Brown never said." Mr. Morven said.

The students turned to each other in confusion but got out of their seats anyway to make their way to the gym where the assembly was being held.

Once in the gym, the students saw Japanese men with leather jackets with the words Blue Bird in front of the jacket on the stage, and news crews, confusing Luz and Connor as all the students took their seats as Vice-Principal Delgado stood at the podium with the microphone"Everyone settled down. The assembly is about to begin." Vice-Principal Delgado said as Principal Brown took the stage.

"Now I am sure that both students and teachers alike are curious as to what is going on. And to let you all know, there's a terrorist group known as the Neo-Deadman's that has appeared here in Gravesfield." The students and teachers all gasp and talks begin to stir in the gym before the Principal continues.

"I understand that this is very hard and difficult to accept. But that is why the members of the Japanese defense organization, Blue Bird, have arrived to help put everything back in order with a brand new project that they are going to be introducing to the school and the public, hence why the news crew is here." Principal Brown said as Geroge took the stage and walked over to the podium.

"Good Morning! I'm Geroge Karazaki! Also known as, Kamen Rider Juuga!" George said while doing a Kamen Rider Ichigo henshin pose before clearing his throat and continuing "The reason why Blue Bird is here in Gravesfield is because we are looking for someone willing to become a new Kamen Rider!"

George uses his watch to show footage of Daiji's brother, Ikki, as Kamen Rider Revice, and his demon partner, Vice "Unfortunately, thanks to the Neo-Deadmans, me and my comrades are unable to transform and defend you all. But that is why I have refined the Revice Driver to find someone that is both strong enough to handle the Revice Driver & the Owl Vistamp and has a demon inside them." George said as Hiromi then spoke through the microphone while standing next to the Revice Driver.

"We created the Kamen Riders to protect humanity from organizations like the Neo-Deadmans. We will make sure that everyone stays safe." Hiromi said.

Luz and Connor were walking out of the gym when Connor saw George "Cousin George!" Connor yelled.

"Cousin Connor!" George said as the two ran towards each other and hugged each other.

"Why didn't you tell me you were here? I could've visited you!" Connor said.

"Sorry! I was busy." George said when he saw Luz "Oh, Good morning!"

"Oh, hi," Luz said with an awkward smile.

"Please stand up straight when he's talking to you."

"Not now…" Luz said to the creature in a hushed tone.

"I'm sorry?" George asks.

"Oh! Sorry! I, uh, talk with myself now and then." Luz said.

"I see. Hey, I saw that you were with my cousin." George's face painted a playful grin "Are you Connor's girlfriend?"

"George! We just met! And we're classmates!" Connor yelled.

"I was joking! Don't be serious." George said.

"A-Anyways, we should head back to class. Right, Connor?" Luz said as she walked away.

At the Noceda residence, Luz was scrolling through information about the Kamen Riders in Japan when the creature appeared again "I see you are doing more information about these 'Kamen Riders' when you should be doing homework." The spectral being said.

"I need to know more about them." Luz puts down her phone and looks at the spectral being "...I got a question for you."

"An Inquiry, you say? Very well, what is on your mind?"

"Are you… a demon?" If the spectral figure had a mouth, she would be smiling.

"It seems like you figured it out. Yes, I am indeed a demon. Your demon to be more precise." The spectral demon said, catching Luz off guard.

"My demon!?" Luz yelled in shock.

"Correct." The spectral being sees that Luz is still trying to comprehend the idea that she was Luz's demon "I'll leave you alone if you need time to process." The spectral demon disappears, leaving Luz alone to grapple with this truth.

The next day at school, Luz was staring out the window when Connor tapped her shoulder "Luz." Luz jolts in her seat.

"Noceda? Are you okay?" Mr. Morven asks.

"Y-Yeah. Sorry, I didn't get much sleep last night." Luz said. She still couldn't believe it. The thing that she thought was a ghost was actually her own demon. It was still so hard to believe.

"Well, can you stay up long enough to stay caught up with the lesson?" Mr. Morven said.

Luz nodded but then the classroom could feel a large tremor underneath their feet "Is everyone okay?" Mr. Morven asks.

"Was that an earthquake?" Luz asks.

"We're not near any faultlines," Connor said when everyone in the classroom heard people screaming.

"What was that?"

"Let's check it out!"

Most of the students leave the classroom "Wait! Everyone needs to stay inside the classroom!" Most of the students were too curious to care but then they saw other students running from monsters that looked like skeleton-looking demons.

"Wah! Monsters!?" One of the students shouted as most of them began to evacuate from the classroom but Connor didn't move.

"The Revice Driver…!" Connor begins to sprint towards the school gym.

"Connor!" Luz shouted, following after him.

Luz sees the chaos that was erupting in the halls of her school, monsters everywhere, smashing lockers "This is crazy!" Luz said as she saw Connor grabbing the Revice Driver and the Owl Vistamp. However, Luz sees another being behind Connor when Connor turns to her when he sees her.

"It's okay, Luz! The Driver and the Vistamp are safe!" Connor shouted.

"Behind you!" Luz shouted back as Connor turned around and saw an origami-like humanoid wolf.

"Oh… crap." Connor is grabbed by the collar of his shirt and is thrown in Luz's direction, the two bodies colliding with each other.

"Ow…" Luz gets Connor off of her and Connor gets up and sees the monster was heading towards them.

"Hurry! Grab the Driver and Vistamp and let's get out of here!" Connor said as he and Luz made a mad dash to get out of the building, with the monster chasing after them.

Outside, Principal Brown and the other teachers saw Luz and Connor coming out of the building "We went back to grab this! But everyone better start running!" Connor warned as the wolf monster came out of the building with a young man right behind him.

The young man had black hair with blue tips and brown eyes. He was wearing a black shirt with a black tailcoat, black pants, and black boots.

"AHAHAHAHAHAHA!" The young man starts laughing maniacally before turning to his fellow students "This school will finally crumble, and society will soon join it! HAHAHA! Gracias, Neo-Deadmans!" The boy shouted as George and his fellow former riders came on the scene with Blue Bird troops.

"Surrender the Vistamp! Immediately!" Hiromi said but the young man only glared at him, pulling out another Vistamp and pressing the button on top.

"JUNIOR!"

The young man then presses the stamp on the ground, creating the skeleton monsters from before "Giff Juniors?!" Hiromi exclaimed as the Giff Juniors started to rush down the stairs, wielding their blades around, trying to hurt the students and teachers alike if not for the Blue Bird troops blocking their attempts.

In the scuffle, Luz and Connor were trying to hide both themselves and the precious cargo they had with them "What do we do!?" Luz asks Connor.

"I'm not sure. I've heard stories of the Deadmans back in Japan but this is a whole new level." Connor admitted when the Wolf-Deadman appeared before them and once again grabbed him by the collar of his shirt "Oh come on! Would it kill you to spread the pain around!?"

The young man then walks up to the three with a sinister smile and two of the Giff Juniors "If you don't like that, I'm more than happy to spread the pain more." The young man said.

"I was kidding!" Connor said. Luz tries to run up to him but is stopped by the Giff Juniors.

"Leave him alone! He didn't do anything to you!" Luz shouted with the young man turning to her with a blank, yet terrifying expression.

"Oh? See that's the thing, he is a part of this school. And… hehehe… I plan on destroying this school, this school, hell this whole town, is as rotten as the rest of society. Don't you see? There's no point in holding back your true self!" The young man said.

"¡Loco hijo de puta! You don't know me!" Luz shouted as the Giff Juniors grabbed her and lifted her up.

"What's there to know about you, Luz Noceda?" Luz looked at him with confusion. How the hell did this guy know her name?

"How do you know my-?"

"You see Luz. I hear many things from the students of this school and they all tell me that you're a loser who has no backbone. You don't do anything to change your situation. You just stand there while others trample all over you. Unlike you though, I now have the power to make everything better!" The young man laughs maniacally as Luz looks down at the ground, realizing that he is right.

All her life, Luz was picked on for just being herself and everyone around her called her a "weirdo", a "freak", or a "Luzer", and sometimes, Luz wondered if it was wrong to be herself.

Before Luz could pounder this more, she heard a voice "Are you really going to give up?"

Luz saw the spectral demon again but frowned "He's right about me… all my life everyone never cared about me… no one wanted to be my friend because I was 'Weird'. No one would ever accept me." Luz said, sounding like she really was going to give up.

"That's not true!" Luz and the spectral demon turn to Connor "I'm willing to be your friend!"

The young man once again maniacally laughs "Y-You!? You want to be her friend? HAHAHA! That's hilarious! You've only known her for a day!" The young man said.

"True. But that's long enough to know that Luz isn't a loser! It's people like you who don't give her the chance to show what she's really made of!" Connor said.

The wolf Deadman then punches him in the gut and throws him toward the Blue Bird troops and Hiromi "Connor!" Luz shouted.

"So… what will you do, Luz?"

"Huh?"

"Death awaits both you and the people of this school if you do nothing. Do you really think that being yourself is strange? Do you detest yourself that much?"

Luz then looks up at the young man and glares "No… I don't! I just want to be understood… I want people to understand me as a person! That's what I want!" Luz shouts as she swings her elbow hard and kicks the Giff Juniors enough to escape their grasp.

"Then… let us forge a contract. I will give you the power to break through this crisis. In return… I simply want to be free from your body every now and again." The spectral demon said but Luz turned to them with a serious face.

"How do I know you won't hurt anybody when you're free?" Luz asks.

"Because… there are no lies in the words of demons. I solemnly swear that I will fight alongside you to protect the weak and innocent." The spectral demon said.

"Okay… I trust you." Luz said.

"Then we have an accord." The spectral demon said as she fades into Luz's body when Luz slaps the Driver around her waist.

[Revice Driver!]

Luz then takes a deep breath and presses the button on the Vistamp.

[OWL!]

A glass wall appears behind Luz, showing texts between her and her demon like a text chat. Luz then presses the Vistamp against the Vistamp Go Slot, showing an imprint of an owl and music begins to play.

[Come on! OW-OW-OWL!]

The Driver repeats the chant as Luz then puts the Vistamp into the slot on the other side of the driver and smirks while doing a pose that looks similar to Ikki's as her demon carries a large empty version of the stamp while floating around her before shouting:

"Henshin!"

Luz then tilts the Vistamp to the right while in its slot and it retracts back to its proper place.

[Buddy Up!]

The demon then puts the large stamp over Luz as it fills up with liquid of the Owl's DNA, transforming Luz into a Kamen Rider.

Luz's rider suit is mostly purple and white with linings of a metallic blue. Her helmet resembles that of an owl with a tail coat piece, the breastplate armor with the emblem of the Owl Vistamp, and the rest of the suit still follows the color scheme.

[Fantasy!]

[Destiny!]

[Dreaming!]

[Flying! Soaring!]

[Kamen Rider! Casti! Ella! Castiella!]

The genome breaks away revealing Luz and her demon, also in a little bit of armor now with the same owl symbol on her chest and an owl-like hood with large scarf-like wings on her back.

Connor and the other students looked on in awe and shock. Even George and Hiromj looked on in shock.

"Luz…!" Connor mumbled under his breath.

Casti looked at herself and noticed that her regular clothes were replaced with the rider suit and that her demon now had a physical form.

"Whoa! Did… did I just become a Kamen Rider?!" Kamen Rider Casti asks.

"It would appear to be the case. But enough chatter for now…" The demon said as they noticed that the Giff Juniors were now surrounding them "It seems we have work to do." The demon said as they began to fight them off.

Casti starts the fight by doing a dive kick against one of the Giff Juniors and punches another one across the face. Another one appears and tries to stab her but Casti dodges out of the way and does a twirl kick to the faces of multiple Giff Juniors around her.

"My… You think there would be an elegant way to fight. Oh, wait. There is." The demon calmly walks towards the Giff Juniors before grabbing two by the arm and twirling them and having them fall to the ground before twirling a Giff Junior and kicking them into a few more.

As Casti fights against the Giff Juniors, George runs up to her "Hey! Spanish Girl!" Casti turns to him.

"Um… could not call me that, please? That has a lot of uncomfortable implications." Casti said as George gave her a new stamp.

"Press the stamp on your hand," George instructed as Casti did so.

Coming from the stamp is a purple chainsaw sword with blue highlights. Casti then inserted the stamp into a port that was under the actual blade "Whoa! A sword came out of that stamp! That's so cool! I think I'll call it… the Demonizer Blade!"

Casti then begins to swing the sword around the enemies, managing to slash across the chests of a few Giff Juniors. Casti then takes the stamp out of the slot and presses it against the same reader system that was on the Driver.

[Stamp By!]

"Get out of the way!" Casti warns the demon.

"For what!?" The demon exclaimed.

Casti twirls around with the blade as energy projectiles come out of it, the female demon was able to dodge out of the way, the projectiles eliminating the rest of the Giff Juniors.

"My goodness. A little more warning would be nice." The demon said to Casti.

"¡Lo siento! But we make a great team though, right?" Casti asks.

"I suppose so." The demon said as she grabbed the sword from Casti's hands.

The wolf Deadman runs up to them, swinging its claws wildly at the two, while Casti and the demon are able to dodge most of the flurry of strikes.

Casti then notices the owl symbol on her chest is glowing "Wait… Could it be that I can…" Casti then takes the Vistamp out of its slot and presses it against the symbol, transforming Casti's feet into sharp talons.

"Oh yeah! Now we're talking!" Casti jumps high into the air before doing a dive kicking into the wolf Deadman and knocks the demon back to her partner.

"Allow me, my dear!" The demoness then swings the sword like a baseball bat and damages the wolf Deadman.

The wolf Deadman struggles to get up as Casti and the demon turn to each other "Let's finish this." Casti said.

"I concur, my dear. It's time for this demon to be punished!" The demon said as Casti tilted the Vistamp twice, the two jumping high into the air.

[Owl! Stamping Finish!]

Casti and the demon perform a skydive kick, better known as a Rider Kick, the power of the genome launching them into the wolf Deadman hard enough that it could feel its energy slowly fading "Your time is up." Casti said as the wolf Deadman explodes behind the two.

Casti then turns to Connor and runs up to him "Connor!" Casti calls out as she runs to see if he is okay with her demon following her.

"It took you this long to check up on a friend?" Connor joked as he and Casti shared a hug when they heard someone clapping.

"Congratulations! Kamen Rider Castiella!" George said, leaving the pair confused.

"Castiella?" The demon tilts her head.

"You are Ella. The Spanish Girl is Casti." George clarifies.

"Casti… I like that." Casti said as she tilts the Vistamp again and takes it out of the slot, allowing her to return to her civilian form and Ella returning to being a spectral being again.

Ella then looks to Luz and Luz looks at the Vistamp before smiling "A deal's a deal." Luz said as she pressed the Vistamp against her chest again, allowing Ella to return to her physical form.

"Wait! Won't your demon try to hurt someone?" Mr. Morven said.

"Bite your tongue! I have standards! Honor! Manners! A lady of my caliber would never stoop so low as to stab others in the back." Ella said as she and Luz glanced at each other, both of them not showing a hint of malice or distrust of the other.

Luz and Ella were in Blue Bird transport to take her home, with George, Daiji, Hana, Takumi, and Hiromi "Well, this has to be the most awkward bus ride I've ever had." Luz remarks.

"Sorry. Since you're in high school still, I feel it's only right to explain what happened to your mother. Since, in essence, you and your demon will be working with us to stop the Neo-Deadman. Wherever they are." Hiromi explained as the transport stopped in front of the Noceda Household.

Luz and Ella place cups of water in front of the members of Blue Bird and Camilla "I can't believe my daughter is now a superhero working for an organization and her partner is a demon. A kind demon, but a demon nonetheless." Camilla said.

"Thank you! …I think," Ella said as she took a seat.

"I understand your concern. But your daughter is the only one who can use the Revice Driver." Hiromi said.

"Not only that, but it's DNA-locked. This means your daughter is the only one who can use it as of today." George explained, making Camilla shift in her seat before Daiji decided to speak.

"I get that you're worried about your daughter. My mother, including my brother and I, didn't react very well when we learned that my sister had a driver, but when she saw that my sister could protect herself with her own strength, we came around." Daiji explained.

Camilla sighs and turns to Luz "Can you promise me that you'll be careful when you're doing this 'Kamen Rider' thing?" Camilla asks.

Luz gives a sincere smile "Sí, Mamí. I promise." Luz said as the two shared a nice embrace before Camilla turned to Ella.

"Now. You promise me that you'll protect my daughter no matter what got it?" Camilla asks.

"Of course. After all, if Luz dies, i die." Ella said as she and Luz shared a handshake.

"This is gonna be the best school year of my life!" Luz exclaimed.

Meanwhile, in a cell at the American Blue Bird HQ, the young man stares at the window of his cell and smiles "They think they can lock me up and throw away the key, huh? HA! I'll get out of here and soon society will crumble before me!" The young man begins to laugh maniacally, creeping out the security guards.

Elsewhere in a nightclub, people and Giff Juniors were dancing and cheering as Ortega took center stage "My family! As many of you already know, our brother, Mason, has been taken by Blue Bird. His sacrifice shall be mourned. However, we will still attempt to make this world ours!" Ortega causes the crowd to cheer as two more people come onto the stage.

One of them was a girl with auburn hair that was entirely pulled back into a curly ponytail with a black ribbon and red rose while wearing rose earrings. Her red ruffled dress has pale pink lining and black fabric beneath it, a large red rose on the left hip. On the navel is a pink and gold heart with a red and magenta ribbon beneath it. Her shoes are black heels with a bow foot strap and ruffled red sleeves with black cuffs.

The other was a young man, who had black hair with streaks of gold and wore a sombrero, a black suit with shoulder frills, black shoes, and a red tie. The suit also had swirls of red and the sombrero also had shades of red and black.

"We no longer have to pretend we don't see things. It'll soon be time for Senor Ortega to rule this world!" The young man said.

"Well said, Luis," Ortega said as the girl clung tightly to him.

"And we'll rule this world together, right?" The girl asks with a smile.

"Of course we will, Mi Amor," Ortega said.

"Behold! The fiance of Senor Ortega! Marcella!" Luis introduces the girl, prompting her to wave at the crowd who was cheering for her and Ortega.

"Soon, my family! The world will regret rejecting us! It's time for humanity to evolve once more!"

"GRACIAS! NEO-DEADMAN!" The three said together as the crowd cheered louder than ever.