Hey everyone I hope you all enjoy this story. After reading a few Ben 10 Rosario + Vampire stories I wanted to try my hand at one.

This does use an OC instead of Ben or Tsukune.

Disclaimer: I own my OC only everything else belongs to their respected creators and owners.

Chapter 1: New Plumber and Vampire

Driving down a paved road in a rural are in Japan was a school bus, but this bus was strange in a lot of ways. It has six wheels instead of the usual four. The stop sign also looked to be in the shape of a pumpkin, as well as have a Jack O' lantern face on it accompanying the word 'STOP' on it. And the grill of the bus's front was shaped like a toothy demonic grin.

The bus itself wasn't the only thing that stuck out the driver was dressed in a professional bus driver's attire, a blue suit and hat. However, he's clothing seemed a bit torn at the corners, and the shoulders were covered in dust and cobwebs. The man was very lanky and his posture was hunched over, and his face seemed to be half covered by the shadows but no enough to cover the thin mustache he had. Also, jutting out of his mouth was a large cigar that he would take a huff of every now and then.

Sitting in the back was a teenage boy at the age of sixteen, moderate height, Caucasian American, with messy short black hair, and brown eyes. While he appeared to be skinny he did have some muscle from his hard training regiment. He was dressed in a white button up shirt, with a red tie and green jacket, along with a pair of khaki white pants and white and black sneakers. But the oddest feature he wore was a small green bracelet that looked mechanical, with a strange black and green hourglass symbol on it, that was on his left wrist.

The boy was Jake Mension.

Now, your probably wondering what an American boy was doing in Japan. That's a simple matter to explain.

Flashback...

Jake was standing inside the Plumber base that resided under the town of Bellwood. He was there because he was called by Max Tennyson to recieve an important assignment. And the new Plumber was excited to hear what his assignment was.

"Japan? Why on earth am I being sent to Japan?" questioned Jake.

In front of him, Max Tennyson, let out a sigh.

Max was a heavyset man with short gray hair. He was always wearing Hawaiian shirts, which was usually a red shirt with gray and violet Hawaiian designs.

"Listen, Jake this is a very important matter." Max told the teenager. "Now, you know that Plumbers are meant to protect Earth agianst alien attacks. Well, aliens aren't the only unkown thing out there."

Jake just cocked his head to the side and went 'Huh?'

"You know those monster movies and books and whatnot?" Max asked Jake, which he nodded his head 'Yes'. "Well, they are real."

"Seriously!?" Jake shouted.

"Yes. Now, let me finish." Max told him. "We Plumbers have know of monsters or 'Youkia' as they prefer to be called, for a while but have been busy with alien activity to really look into them. And now thanks to my grandson Ben, Earth is having a lot more peace with aliens then we've had in years. So, we decided it was time to help bridge the gape between humans and youkai." Max explained.

"But, how does sending me to Japan help?" Jake asked.

"Our intel tells us that a school known as 'Youkia Academy' is located within Japan. We plan on sending in someone so they can learn about the youkia and hopefully let youkia know that humans are ready to make peace with them." Max replied.

"So, you want me to attend this school learn about youkia and bridge the gap between humans and youkia? Easy." Jake said.

"Not so fast." Max interupted. "The things is our intel also says that the academy itself doesn't allow humans and even has a a rule that allows them to execute any human that comes there."

Jake's eyes threatened to pop out of his skull when he heard that. "What!? Then how am I suppose to go to the school then?" Jake asked.

"Simple." Max answered. "We're going to make it seem like your a youkia."

"And how do you plan on doing that?" Jake asked, extremely confused right now.

"We're going to give you some alien DNA, so that you seem like an actual youkia." Max answered.

"Are you crazy! No way am I going to let you experiment on me! If you need someone to look like a youkia then send Ben." Jake shouted.

"Calm down, Jake. We aren't going to experiment on you." Max replied trying to calm Jake down. "And we can't send Ben he is busy with more important problems to be helping us with this problem."

"So, exactly how do plan on giving me alien DNA?" Jake asked.

"I believe I can answer that." came an old rasy voice.

Jake turned around to see a small gray like alien, with large green eyes, and strange whisker like things on his face. He was weaing a black and green like lab coat that had some metal plating on it.

The creature was none other than the Galvan known as Azmuth, the creator on the Omnitrix, the most powerful thing in the universe.

"A...Azmuth!" Jake shouted in shock, very few people have ever seen Azmuth so this was a suprise. "What are you doing here?"

"I'm here because this old cogger talked me into something I know I'm going to regret." Azmuth answered while shaking his head back and fourth.

"Hey! Your over a thousand years old. So, don't be calling me old." Max said.

"Can we get back to the whole 'helping me blend in with a bunch of monsters' plan here?" Jake asked in a sarcastic voice.

The two old geezers stop their bickering and stared at Jake for a second.

Azmuth then cleared his throat. "Ahem. As I was saying I honestly think that this is a bad idea, Tennyson." Azmuth said while sending a small glare towards Max.

"Azmuth, you know that your assumptions aren't always right. Look at what Ben's become. You thought that the Omnitrix could only be used as a weapon and Ben showed that it can used for good. So, trust me and my grandson on this." Max lectured at the small galvan.

"Can someone explain to me what you two are talking about!" Jake shouted in annoyance.

The answer he got was Azmuth stepping to the side of the table he was standing on to show a small green bracelet that looked mechanical, with a strange black and green hourglass symbol on it.

"Is that...an Omnitrix!" Jake exclaimed. "Then...you want me to..."

"Yes and No, we want you to put this modified Omnitrix, or as Ben calls it the 'Monsitrix', on and enter 'Youkia Academy'." Max explained.

"Modified?" Jake question.

"Allow me to explain." Azmuth answered. "This Omnitrix only has six alien DNA strands in it, selected by me, Max and Ben just for this mission. So, what's in it is what you got, understand?"

Jake nodded his head in understanding.

"Good, now on to a bit more complex matters." Azmuth continued to explain. "I'm sure you know that Ben's Omnitrix scans new foreign DNA that isn't recorded into the Omnitrix. This one however will not."

"Why?" Jake curiously asked.

"We can't have you changing into some of your classmates. We want to pass you off as some monster that can take multiple forms. If they see the Omnitrix scanning them and then you being able to turn into the creature that they are. Then things will become troublesome." Azmuth explained.

"Azmuth's trying to say that we're hoping that we can pass the Omnitrix as some kind of limiter or something that allows you to control your many different forms." Max explained in simpler terms.

"I just said that." Azmuth remarked, but continued on explaining the modifications he made. "I however, could not remove the feature entirely, if I got rid of that feature then this wouldn't be nothing but a piece of high-tech jewerly. So, I made it were it requires an actual drop of blood on the faceplate for the Omnitrix to add the DNA to it's database."

"Why blood?" Jake asked.

"Because, blood is a lot harder to get from people then hair or even having someone grab it with their bare hand." Azmuth answered.

"Ok, I think I get it all." Jake said as he grabbed the Omnitrix and slapped it on his left wrist. "Now, let's see what forms I have!" he exclaimed, as he raised his hand to activate his Omnitrix.

All of the sudden something grabbed his had and he turned to see it was Max.

"Hold on there." He told him. "We need to get you ready for Japan first."

And with that Jake spent the next month and a half learning Japanese, how to read and write kanji, and all about thier culture.

Flashback End...

So, that's why Jake was on this bus in the middle of Japan.

Right now though, he had his nose in a book that Max had given him before he left.

The book itself was an amazing for him to have. It wa a book that had all the information that the Plumbers had on the few monsters that they have encoutered and a few theories that a Plumber by the name of Ryan J. Munster had in it.

'It's amzing that a few of the monster that exsist are actualy from aliens.' Jake thought.

He had learned the Mermaids are actually a byproduct of Piscciss Volanns(Ripjaws) mating with humans. Also, Yetis and other Bigfoot like monster are believed to be a mutation of Gimlinopithecuseses(Shocksquatch) that have strange fur coloration and have lost thier electokinetic powers.

Also, Loboans(Benwolf) are actually from Werewolves that were exposed to Corrodium. Lastely, Ryan J. Munster had a theory that Witches and Wizards are from an extinct alien race that came to Earth and mated with humans. But, it could never be proven if it was true or not.

All of the sudden Jake was brought out of his reading by the bus driver's creepy voice.

"So… you gonna be a freshmen in Youkai Academy, eh?" the driver asked.

"Yes, sir." Jake answered.

The driver then let out a light chuckle as he spoke up once again, "Then you'd better prepare yourself mentally. It's not exactly a school for the faint of heart…" he turned his head to the side. Jake didn't see it, but the man's left eye glowed an eerie yellow as a smirk showed up, "… especially for any unprepared human who comes wandering in there."

'Wonder why.' Jake thought. 'Can't be as bad as the Pumber Academy.'

The bus suddenly entered a long dark tunnel, it wasn't long thought before they left the tunnel.

The bus driver opened the door to let Jake off. Once he was off Jake took in his surroundings.

There was grim sky and a scraggly forest in view. Next to him was a scarecrow-like sign which had the name 'Yokai Academy' written on it in Japanese. The nearby forest was leafless and every tree looked dead. Behind the young man was a cliff which dropped into the ocean.

The closing of the bus door caused Jake to turn around in time to see the bus drving away.

"Guess I don't get a chance to change my mind." Jake commented sarcastical. "Might as well start making my way to the school."

And with that Jake began walking throught the dead-tree forest.

Of course, the forest was even creeper from the inside. It was littered with tombstones and add all the creepy devil crows that were giving him the eye. This was something out of a horror film.

"Max could have warned me that this place was super freaky." Jake mumbled to himself.

He was brought out of complaining when someone shouted.

"Look Out!" came a femal voice.

Before Jake could even react something barreled into his back sending him and the rider flying forward.

'Great only here for five minutes and something bad happened.' Jake thought to himself as groggily began to stand. "Hey, you ok?" he asked the biker.

"Yes, I'm fine." came the same female voice that had called out before the bike ran into him.

It was then that Jake got a good look at the girl that ran him over.

She had alabaster skin, and looked to be aound sixteen years of age, with a very pretty face with long pink hair that went down her back, a few bangs brushed to the right, with a slim and slender figure, and wearing a uniform similar to his, except with a short green plaid skirt. But her most distinguishing features were her aquamarine eyes that nearly sparkled as the light touched them, and the leather chocker that had a silver cross hanging from it and beads connecting from the chain to the choker that she wore around her neck.

Jake was in shock to see such a beatiful girl that he almost missed hearing her apologize for running into him.

"I'm sorry. I'm a little anemic so I sometimes have fainting spells." the girl explained.

Jake just waved his hand. "Hey, it's alright. I've experienced worse." he told her. And that was the truth. His Plumber training was the toughest thing he ever had to experience in his life.

"Let me help." Jake said as he walked over to her and helped her up.

"Thank you." the girl said as she smiled at him, as he helped her up.

All of the sudden though her eyes seemed to glaze over as she stared at him.

Jake noticed this and was worried that something was wrong. "Are you okay?" he asked her once again.

The girl released a sigh as she answered him. "Yes." Then all of the sudden her eyes widened slightly. "Oh no, your bleeding!" she exclaimed.

Jake wondering what she was talking about rubbed his cheek and noticed that she was right as a bit of blood was now on his hand.

"Huh, I wouldn't worry to..." Jake began to say but stopped when he saw that she had apparently pulled out a hankerchief to wipe the blood away, but she seemed to be frozen.

Before Jake could even ask to see if she was alright she walked up towrards him so the were face to face.

"You smell so nice." the girl said in a dazed voice.

Jake didn't know exactly how to respond to that, but he didn't have to worry about that as the girl moved even closer to his face.

"Whoa! Wh..what are you doing?" Jake asked in shock.

"I'm sorry. But..." she said as she moved closer and opened her mouth actually showing she had some small fangs. "I'm a vampire."

CHUUU!

Jake was shocked at first, but that quickly wore off as he realized that some random girl was bitting his neck.

Luckily, for him the girl quickly let go of his neck and stepped back. Her face a bright red with embarrassment.

"I'm so sorry!" the girl blushed profusely, acting embarrassed about him. She fidgeted with her fingers, smiling embarrassed by what she had done. "It's just… well, your blood smelled so nice, and I couldn't help myself! I really am sorry!"

Jake just felt where she had bite him and couldn't fell any sort of wound or anything so he didn't think he should barate her over it.

"It's fine." he told the girl.

"I'm Moka Akashiya by the way." the now named Moka introduced herself.

"I'm Jake Mension." Jake told her. "I did do the introduction right didn't I?"

Moka tilted her. "Your not from around here?" she asked.

"Nope. From the USA." Jake asnwered. And unfortanelty, his curiosity got the better of him. "Are you an actual vampire?" he asked.

"Yes," Moka nodded shyly. But rather, it seemed like she looked a bit worried if he would give her the wrong answer, "Do you…hate vampires?"

He seemed a bit surprised by that question, but answered truthfully to her. "I've never met a vampire until today. So, I can honestly say I don't." he answered.

The next thing he knew he was in a hug from Moka. "I'm so happy!" she exclaimed. "Do you want to be friends?" she asked him.

"Yeah, having some friends is going to help me out a lot. Considering I'm along ways from home." He answered.

"That's true." Moka replied realizing that Jake would have a lot harder of a time making friends than her.

And with that the two new friends began walking towards the school was a combination of castles mashed together, and was as large as ten football fields. With its six story window doorway and impressive six story height, it would have passed on as a college to anyone else. There was even a huge clock tower in place in the back, for all to see the time and heard the chime of the bell goes off as soon as the Class Bell would go off.

Eventaully, Moka seperated from him to go to the Entrance Ceremony. She did promise to meet up with afterwards though.

After the entrance ceremony Jake was sitting in his home room resting his head in hand. When the door opened and in walked in a woman. She was wearing a sphaggeti strap and skirt on. Her hair was blonde but tufts of it resembled cat ears.

"Hello, everyone and welcome to Youkai Academy!" she said. "I am your home room teacher, Shizuka Nekonome!"

Jake could already tell he was going to like her as a teacher just by the way she acted.

"I think you all already know this but," Nekonome said. "This is…a school built for the sake of monsters to attend and learn to coexsist with humans." When she finished that sentence a tail popped out from under her skirt.

Jake looked down at the Omnitrix thankful that he was actually given the device so he could attend the school with no problem.

"But sensei," a kid growled. "Can't we just eat the humans? I could start with the cute girls." everyone turned their attention to a boy, around sixteen, built like a line backer, and dressed in biker gear of sorts. He had brown hair slicked back, piercing on his face, and kept licking his lips like some kind of sicko rapist.

When Jake got a good look at him he knew good and well that he and the guy might be gettingn into a fight. He also knew that this is one of the guys that Max wanted him to report.

Jake wasn't just sent here to learn about youkia and bridge the gape between humans and monsters, but to also keep an eye out for any monsters that could pose a threat in the future.

"That's silly!" Miss Nekonome sighed. "You won't be finding any humans here! All of the faculty and students are monsters!"

Jake had to try his hardest not to snicker a ther comment. 'If only she knew.' he thought.

"And even if a human wandered in here through the barrier that protects this school… " Miss Nekonome explained, but still with a smile on her face, "… they would be put to death."

Jake's eyes widened to a large degree. Even if he was told that was a rule it was still shocking that a school that was supposed to promote peace would kill anyone of the people they were trying to get along with.

"Well, say what you want," the guy said, "But ever since class started I've been smellin' a human in here the whole time."

Jake had to make real sure that nobody noticed him flinch when the guy said that. He was going to have to be even more careful now that he knew monsters could smell his human scent.

'Got to let Max know that bit of information.' Jake thought while making a mental note.

"After the entrance ceremony I kinda got lost in the school," a familiar voice said. "Sorry I'm late."

"Oh that's fine," Nekonome said kindly. "Just take a seat."

"Ok!"

Jake looked up. Much to surprise. It was none other than Moka.

"Who is she?" some other guys said. "S…such flowing hair. Big eyes!"

"Whoa, beautiful!" another guy said. "Even if it just her transformation, there isn't anyone who could transform into such a beautiful girl."

"She's too hot!" the boys cried. "I'm so happy to be in the same class as this girl!"

Jake frowned. 'Perverts.' He thought to himself. "Hey, Moka." he said.

Moka blinked. "Huh? Ja…Jake?" She looked in front of her and saw him sitting there. Suddenly she flew at him and wrapped her arms around him. "It's Jake! We're in the same class?" she asked excitedly as she hugged him in joy.

"Hey! Who is that guy!?"

"How does a gaijin rate a hug!?"

"Just who is this guy!?"

"What relation does he have with that girl?"

After class, Jake felt really awkward. Moka was dragging him through the school, her arm wrapped around his arm. She was being a little forward than he was used to. He shot a look at Moka. She looked really happy, like a little kid in a candy factory. He found it incredibly hard to believe she was a monster.

"Hey, hey!" Moka said. "Isn't this a cool hallway?"

"Yeah." he said he was still pretty uncomfortable after what he heard in the homeroom.

They continued walking, but as they did they attracted alot of attention well, Moka did anyway.

"Hey! Did you see that girl?"

"Whoa beautiful! I've never seen such a hottie!"

"I…I wanna date her!"

"Hey! Who's that guy next to her?"

"Perhaps he'll leave on his own?"

"If not, then that jerk is dead!"

"Let's just kill him right now."

Those comments really worried Jake he wasn't sure if they were going to try kill him over Moka or the fact that he was a foreigner. When, he was learning about Japanese culture he found out that they weren't exactly happy with foreigners.

Jake and Moka soon stopped at a vending machine for some drinks. When the drinks fell out, the two simultaneously reached to grab their respective choice. Though their hands slightly brushed each other, they both pulled back. Not from the drinks but from the touch; it wasn't an act of hatred as Ben thought as he blushed a bit from the experience, as he looked to Moka, who was equally blushing.

She turned to him, and smiled, "Oh, Jake. You're silly." And playfully pushed him.

However, Jake didn't count on the strength in that push, considering he crashed into the wall. Nearly feeling like he left an imprint in there, he got up and rubbed his soaring backside, 'Yeah… she doesn't look it, but she's really strong.'

After a moment of recovery, they got their drinks any way and sat down on a bench nearby. Jake got himself what he could guess was soda while Moka got herself a can of tomato juice.

"So, how do you like Yokai Academy?" Moka asked him.

"I have to say I thought I was going to have some difficulties adjusting here, but it's not as bad as I thought. I'm real glad that I came here." Jake answered.

"I'm real glad you came to." Moka told him. "If you haden't then we never would have become friends."

Unfortanetly, Jake and Moka's moment was ruined by the arrival of the one guy that wanted to eat humans. "Hey, there, Sexy," the boy said as he leaned against the wall with his arms crossed, and looking at Moka. "Moka Akashiya, right?"

Um, thanks," Moka nodded, gulping nervously at this fellow. "And… you are?"

"The name's Saizou. Saizou Komiya," the boy introduced with a grin. "I'm one of your classmates."

"Oh…um," Moka nodded, still feeling rather nervous around this guy. "Good to meet you."

Jake didn't say anything as he glared at Saizou.

"By the way," Saizou grinned before he reached out and suddenly grabbed Jake by the lapel of his jacket. Moka gasped in shock, while Jake struggled with the other teen's strength. "Why is a girl like you hanging out with a complete wimp like this?"

Unfortanelty, for Saizou he underestimated Jake's skills. Jake grabbed a hold of Saizous wrist and squeezed a pressure point on his wrist causing him to let go.

Before Jake or Saizou could even make a move to continue the fight Moka ran over to Jake and grabbed his arm. "I'm sorry, but we're in a hurry! Bye!" She shouted as she drug Jake away.

Saizou just glared at the two disappearing, even as a can of unopened tomato juice rolled to his feet. Suddenly, a long whip like tongue lashed out at the can, and snatched it up. A big gooey splash sound was heard as tomato juice splattered on the ground.

Meanwhile, Moka and Jake were now on the academy rooftop.

"Woo! That was scary!" Moka sighed. She turned to Jake. "Weren't you scared at all?"

"If you saw my drill instructure then Saizou wouldn't even come close to scaring you." Jake answered.

Moka was kind of confused as to what Jake meant, but she didn't bother asking him about it right now.

"Thank you for protecting me, Jake." Moka told him.

"Hey, it's what friends do." Jake replied.

The smile on Moka's face grew even wider at that. "Yeah, but I don't want my only friend to get hurt." she explained to him.

"Only friend?" Jake asked.

Moka stepped forward to stand in front of Jake. She had a shy blush on her cheeks and she averted her gaze. "Well…I'm not too good at making friends," Moka admitted. "And..."

"And...What?" Jake asked.

"You've already let me suck you blood!" Moka smiled with a flush on her face, as she cupped it, trying to hide the blush on it. "You should be proud since your blood is just awesome! The texture, the aroma, the vitality, and there's even something in it I've never tasted before! Delicious!"

"That's the most interisting compliment I've ever recieved." Jake responded with a large sweatdrop.

"By the way, Jake," began Moka. "What kind of monster are you?"

"Isn't that against the rules?" he reminded.

A large blush appeared on Moka's face. "Oh, I forgot all about that. I'm sorry."

Jake gave out a light chuckle at Moka's embarrassment. "It's ok, my situation is very complicated." Jake explained. "But, I do have to say you don't seem like a vampire Moka."

"Oh, that's because of this," Moka said, as she lightly pulled her shirt open to expose a silver roasary with a red eyed gem in the center of it.

However, Jake gulped and blushed as he took notice of what was also there: her cleavage. He stuttered and looked away slightly as he asked, blushing, "Um, what exactly am I supposed to look at."

"The rosary seal attached to my choker," she answered, pointing at the cross hanging from her choker. "If it gets taken off, my true form is released. And without it, I can get Really scary."

"Really?" asked Jake in all curiousness.

"Yes." Moka answered. "But, enough about that. Did you go to a monster school in Amereica?" she asked.

"No, I actually went to a human school." Jake answered.

A frown appeared on Moka's face at the answer. "I hate human schools." Moka commeted.

Jake's eyes widened at that remark. Moka didn't seem like the type to hate anyone or anything, but judging by her reaction she can.

That truely hurt Jake a lot knowing that his friend had a problem with humans.

"I got to go and...unpack, Moka." Jake said as he left.

"Wait! Jake!" Moka called out but she was to late, he was gone.

After all the classes were over Jake wsa outisde the school's main gate holding his backpack with all his belongings.

'I guess I was never cut out for this kind of thing.' Jake thought. 'Maybe next time they'll send someone who doesn't get so emotional.'

Just as Jake was about to leave her heard someone call out his name.

"Jake!"

He turned around to see non other than, Moka. The one person he was hoping didn't see him leaving.

To Be Continued...

I hope you all enjoyed this chapter and I hope you review.

Also, to answer one question I'm sure I'm going to recieve. Yes, Jake will be able to obtain Youkia DNA. But, I will not give away which ones it will be.

The Monstitrix is call ed that for two reasons. One being as the six alien DNA strands in it are related to monsters in some way. The other reason is it will eventauly get monster DNA.

The aliens that Jake possess are Shocksquatch, Ghostfreak, Benmummy, Benwolf, Benvictor, Ripjaws.

Plus, if anyone has any ideas fow possible monster DNA then please let me know

Again thanks for reading and please review.