Hello, this is my first Crossover One-shot, I hope all that read this enjoy it!
Please read and review! This crossover is Blue Exorcist/SerVamp.

Rin Okumura sighed as he walked back to the Blue Cross Academy dorm where he and his brother lived. He had been in a hurry to get the groceries his brother had asked him to, and his two-tailed cat sith familiar followed him to the store.

"Wait here, and I will be back in a few minutes if you wait until I get back to you I'll make sure to get you a new catnip mouse," Rin said as he stood up and started to walk away from the little black and white kitten.
"Okay, Rin I'll wait here, but try not to take too long your brother is waiting on us remember?" Kuro said telepathically to Rin as he sat down next to a fire hydrant in front of the store.
"Oh don't worry, I won't be long," Rin said with a grin and a thumbs up as he headed in.

While waiting on Rin, Kuro heard the sound of a small bell, Kuro turned his head trying to find the sound when he saw it was a brown-haired boy who was about Rin's age who ran past him. Hanging off one of the boy's shoulders was a small black cat wearing a gold bell on a red collar that jingled as they passed. While he watched the duo run past, his ears picked up a bit of their conversation.

"Mahiru could you slow down please, it's not like you to get so worked up over something like this," the black cat cried out as they passed by. The cat's eyes widened as it caught sight of Kuro as he sat there, his two tails swinging back and forth as he waited on Rin.

The brown-haired boy jerked to a sudden stop, almost dumping the small black cat that clung to his shoulder. Wait here, Koro, he said as he paused waiting for the small cat to jump off. The black cat sighed, but he jumped off landin

g close to where the other black cat was sitting next to a fire hydrant in front of the store.
"What's your name ?" Asked Koro as he jumped down from Mahiru and landed almost on top of the other black cat, who after taking a closer look he noticed that it had a patch of gray fur under its chin, it also had a pair of small horns on its head.

"My name is Kuro," the two tailed cat said as it came closer to sniff at Koro, both of his tails were fluffed up and his back arched and fur standing up, looking half scared and half mad.

"You don't smell like a demon, who are you, why are you here and what is your name?" Kuro asked as his tails started to twitch.

"Whoa that's a lot of questions, young one, and what do you mean by demon? Do you mean the dark aura that some people carry around with them?" Koro said as he sat down facing Kuro.

"Wait, do you mean that you can't see them, like at all? Like over there, look at that human standing at the corner do you see the small demon climbing on his shoulder?" Kuro asked as he nodded his head at the middle aged man who stood on the corner waiting for the light to turn.

Koro glanced over at the man that Kuro had pointed out, the man in question was standing at the corner and had a dark Aura around him with his shoulders slumped and head down. While He couldn't actually see the demon in question He could see a large cloud of darkness hovering over the man.

"I guess that you don't have a temptant then," Kuro said with a frown.

"A temptant? What do you mean by that?" Koro asked as he looked over at Kuro with a small frown on his face.

"Oh, do you want me to give you one?" Kuro asked as he looked up at the eldest vampire, Who in turn shook His head with a rueful smile on his face.

"Thanks but no, I'm not interested in seeing even more demons than I already deal with on a daily basis, besides my demons are bad enough I don't need to see more of them." Koro said as sat down tucking his feet under him and wrapping his tail around him as he waited for Mahiru to finish his shopping.

"What do you mean, so can you see demons or not?" Kuro asked as his tails started to thump on the ground in anger, his ears laid back and a growl forming in his throat.

"Not in the way you mean, but each of my siblings and I have our own darkness hovering in the shadows that we have to deal with. Take a look over there," Koro said as he turned towards a dark spot on the pavement that they sat near. From the dark spot a dark blackish/purple rag doll formed from the darkness looking like it was covered in Goo, it turned to face Koro and said, "Oh is this a bad time to talk to you? I can come at another time if you want." It then disappeared and after a few seconds the dark spot was also gone as well.

"W-What was that?" Kuro asked as the fur stood up on his back, at the dark creature as it disappeared from view.

"My Demons." Koro said as he laid his head down and closed his eyes, his ears were laid back and his tail was fluffed up, but he looked like he was trying to sleep.

Oh, okay then, sorry for asking. Kuro said softly as he sat down and waited for Rin to come back.

After waiting in silence for what felt like eternity, even though it was only five minutes, Kuro's ears pricked up as he heard what sounded like his Master Rin.

A few seconds later both Rin and Mahiru walked out together both engaged in a conversation with each other. As they came up to where the cats sat Mahiru glanced at his watch and said.

"Uh oh, we're going to be late if we don't hurry!" He then scooped up Koro and said, "Sorry Rin, but I have to go if I don't I'll be late to an important meeting! It was nice meeting you, I hope that we can meet up at a different time." After saying that, both Mahiru and Koro walked off into the growing dusk.

As he watched them fade into the background, he looked down at Kuro and said, "ready to go back to the dorms?"

Kuro looked up at Rin, but was silent for a few minutes before he spoke saying.

"Sure, let's go home. By the way I might have made a new friend, that black cat that was sitting with me was interesting and some what friendly. I wouldn't mind it if I saw him again at some point. His name was Koro just like mine!"

Kuro said as he walked next to Rin as they came close to the campus and got closer to the dorms. As they came around a corner and almost made it to the abandoned dorm when Rin's twin brother stood in front of them, Yukio looked upset but he didn't say anything, he just sighed and followed Rin and Kuro inside the dark abandoned dorm.

As the door slowly shut, Kuro peaked out at the brightening stars and pondered about what Koro had said to him, specifically the last thing he had said about that Shadow being one of his demons. After a few minutes of pondering he turned and ran up the stairs to Rin's room where he could curl up on top of Rin as he slept.

It wasn't until several months later that he thought of it again, when the local news had covered a story about a huge shadowy like Lion that had perched on top of a skyscraper in the nearby city. At the time none of the demon hunting class could go and try to help with it, they had their hands full with the Pope and the gates of Gehenna being opened. After that battle, they had heard of it but the lion had already disappeared, making many believe that it had been a mass hallucination that everyone had seen.

Part of Kuro couldn't help but think of that time that he had been terrified by a Shadow, and the little black cat that was connected to it.

~End~

A.N. This is my first time writing a One-Shot. Also, it is my first time writing a crossover anime. I hope that all of my readers enjoy it and please follow and review it if you like it! I got this idea when I first watched Ser-Vamp, all I could think of was that there were some similarities in both Ser-Vamp and Blue Exorcist, mainly being that there were two black cats that were both named Kuro/Koro even though both are totally different anime Characters they seemed to be able to live in the same universe which is why I have it like that.