So I just finished watching Blue Exorcist awhile ago and I fell in love with it! So I thought, "Why not write a story about it?" Now be aware that the main pairing here is Rin/Izumo. If you don't like the pairing, then don't read. I don't need reviews saying crap about "Rin should be with Shiemi" and "I hate this pairing, fuck you." I don't need that shit. Anyway, lets do this thing.

Satan looked down at the demon before him. Said demon had large pointy ears, really yellowed fangs, shoulder length, greasy, tangled black hair, and a beard that looked like a crows nest. The demon had huge liquid-like eyes, almost like an insect. The demon wore a light tan trench coat, and was shirtless, revealing abs that all men wish they could have. The demon stood about eight feet tall, with broad shoulders. All in all, the demon was pretty damn scary.

"Is it true, my lord?" Asked the demon. "You have a son?"

"Yes, it's true." Satan answered. The demon's eyes widened, while Satan kept his calm intact.

"But my lord," the demon cried out. "Don't you understand the threat the child can pose?!"

Satan sighed. "I am well aware of the threats he can pose, Beelzebub," he hissed. "But I am also aware of the use this child could give me." He paused, before continuing. "He has inherited my flames, which means he has my power inside him. With proper methods, I can use him to achieve my ultimate goal of merging Gehenna and Assiah together."

Beelzebub clenched his fists, before saying, "Am I dismissed, my lord?"

Satan nodded, and the bearded demon took his leave. Entering the portal leading back to his domain, Beelzebub began to laugh bitterly to himself. 'My lord, what a fool you are. One cannot merge two worlds together.' He thought. 'No, dominating both worlds, is a true goal. And that is mine.' Beelzebub entered his home, and a moth landed on his finger. The demon stared at the small creature, before grinning wickedly. 'This boy, whoever he may be, will be MY path to victory!' Then he began to laugh wildly, as moths, locusts, and flies began to surround him.

Sixteen years later...

A train was passing through a large valley, the chug-chug of its movement sounding loudly. Inside were our favorite little exwires. They had just gotten back from a mission involving demonic wolves. Everyone was doing their own little thing. Except Rin and Bon. The two were in a heated argument, while Shiemi and Izumo, the two unfortunate enough to be sitting between them, stared helplessly. Kuro, tired of the two boys bickering, curled himself comfortably on Izumo's lap. Yukio looked up from his conversation with Shura, who was sitting next to him. He asked them to be quiet, but his words fell upon deaf ears. He sighed, finally giving up. Shura, however, seemed amused by the exwires' argument. Izumo shook her head, trying to get lost within her manga. That plan was destined to fail. Finally, Izumo couldn't take it anymore.

"Both of you better shut up right now, or else I'm going to rip off your balls and shove them down your throat!" She yelled. The boys instantly stopped yelling right then. The pig-tailed girl smirked in satisfaction, and went back to her manga.

Rin stared in awe of Izumo. Sure that outburst was scary as hell, but he still stared at her. He had a crush on her, you see. For the past four months. For some reason, he couldn't help but admire her. He didn't know why, but he was in love with the girl. Izumo looked up, and locked eyes with him. Rin turned away, blushing.

...

The engineer and conductor were playing a card game, not noticing the figure rising behind them. The figure wore ninja clothing, with a sleeveless trench coat with hood over it. He had a black piece of cloth covering the bottom half of his face. He pulled a katana out from its sheath on his back. With one swift motion, he decapitated the two. The assassin walked to the controls, and cranked up the train's speed to the max. He then calmly walked toward the passenger cars.

...

Shima looked out his window, and narrowed his eyes in confusion. He turned to Konekamaru (love that name), who had his head buried in a textbook. "Is it just me or are we moving kinda faster?" The pinkette asked.

Konekamaru looked up from his book. "We are moving faster than usual." He then shrugged. "They probably increased speed a little."

Rin listened in on the conversation. He looked out the window. They were moving kind of fast... Before he do anything, however, someone screamed. Rin whipped his head around, and saw a man clad in black standing in the middle of the car, a katana in his hand. Rin sniffed, and his eyes widened. 'Demon.' He thought. Yukio seemed to sense it quicker, and he leaped out of his seat, drawing one of his pistols. He aimed it at the demonic assassin.

"Who are you?" He asked in a demanding tone. The assassin looked at him, before pointing his finger at Rin.

"I've come for the young prince." He said in a smooth, whispy voice, almost as if he weren't there.

Shura looked out the window. Her eyes widened as she turned to Yukio. "We got a problem," she hissed. "That bastard has sped up the train!"

Rin stood up, staring at the assassin. He pulled out his sword, unleashing his blue flames. "Well here I am," he growled. He turned to his twin. "Stop the train. I'll take care of this guy!" Not giving his brother a chance to answer, Rin lunged at the assassin. He swiped his sword at his opponent, only for him to disappear in a puff of smoke. Rin stared blankly in confusion, before he felt two hands wrap themselves around him. Everything went black for a second, before Rin found himself on top of the train (hell yeah, train fight!).

The assassin offered his hand to Rin, who was lying on the train chest down. "Come peacefully, my prince." He said in a monotone voice. "Let us not fight."

Rin jumped to his feet, before swinging his sword down at the assassin. He caught Rin's sword between two fingers, and thrust them forward, causing Rin to go flying back. He landed on his shoulder hard, and hissed in pain. Before he could get up, the assassin stepped on his chest, pinning him to the spot. "Please don't resist, my prince," he said. "My master wishes for me to bring you to him alive."

Rin grabbed the assassin's foot, and trying to push it off him. "Master?" He asked through clenched teeth. "What the hell are you talking about?" He managed to get the foot off of him, and charged at the assassin. The black clad ninja ducked, though (matrix style). Rin looked up, only to get smacked right in the face by the entrance of a tunnel. Rin fell down, and barely grabbed hold of the edge of the car. He tried to hoist himself up, but the assassin stepped on his fingers. Rin yelped in pain, and he looked up, staring into the killer's eyes. All of a sudden, a gunshot was heard, and the assassin disappeared in a puff of smoke. Rin's fingers began to slip, but his hand was caught. Rin looked up, and saw Yukio hoisting him up. The two collapsed on the train, laying there.

"I didn't kill him," Yukio panted. "He disappeared to fast." He turned to his older brother. "Did you find out what he wanted?"

Rin nodded. "He said that his master wanted him to bring me to him alive." Yukio stared at him in confusion. He was brought back to earth by Rin's voice.

"Yes?" He asked.

"Can we go back inside now?"

So did you love it? Hate it? Let me know! I based Beelzebub's design off of the villain from Men in Black 3, just so you know. I got the inspiration of the assassin from Noob Saibot (appearance) and Smoke (teleportation powers) from Mortal Kombat, and Assassin from Fate/Zero (Personality). I'm just gonna call him "the assassin" for now. But if anyone can think of a name for him just put in a review and that'll be great!