I do not own blue exorcist/ao no exorcist. It is owned by Kazue Kato.

Ten minutes before the goblin incident, Rin and Mephisto arrived at an isolated alley behind the school. Mephisto now in his normal form threw Rin his, as quoted by Mephisto "badass demon king clothes," to try on. Rin slipped on the clothes feeling half ridiculous. His dark hair covered his eyes as he looked up at his new mentor, "What are we doing while my charge is in your little exorcist school?"

Mephisto brought out an ornate key and said, "Well I want my first lesson of how to be a demon to be about how ignorant you are and how you can't trust anybody."

Rin's eyes squinted in distrust and said, "The only thing I don't trust is someone like you."

Mephisto brought up a handkerchief to eyes dabbing fake tears and whined, "Such a cruel thing to say to a person that tells you the truth," He smiles menacingly, "One of the few that actually does. Follow me dear boy."

Mephisto led Rin down to a door of a shed. Mephisto then smoothly slid the key into the door and turned it. As the door opened, Rin became shocked as he same the massive nave hallway in the doorway contrary to the smallness of the shed. The pair strolled in as Rin muttered surprised curses. The demon king of time then led Rin to a classroom. Rin immediately questioned, "Why are we even here?"

Mephisto giggled, "Well my little Satan spawn, as I've been trying to say, I'm here to show you how naïve you truly are. Eins! Zwei! Drei!"

With that, a small chain dropped from the ceiling and Mephisto pulled it. Suddenly the room became dark and the chalk board suddenly became like a window. Rin was now able to peer into the next room, like a one sided mirror in cop shows. He saw several of his classmates, a boy with a puppet on his hand, and a hooded figure playing a video game.

"Wow, it must be easy for you to peek on girls in the locker room." Rin smiled.

"How fun, but we will be peaking on something different from that," Mephisto stated as Yukio walked into the classroom. "The secrets of a brother!"

"Wait what's Yukio doing here?"

"Well you see as a boy your dear little brother received his mashou, which is basically a demon rite that allows people to see demons, from you a demon. Your daddy started training him to be an exorcist at a very young age. He's a prodigy in anti-demon pharmacology."

"The old man taught him! They both hid all of this from me!" Rin grunted clutching kurikara. Mephisto read Rin's body language in glee. His arms were shaking like a dryer and his tail jumped out of his pants thrashing wildly. He also noticed Satan's fire start to burn on his back. The mad hatter smiled viciously hoping for such a reaction.

"Like I've said in the world of demons you can't trust a soul, not even a brother. You are completely blind to the world but I shall be your guide. Now let us continued to watch your dear brother." Mephisto said turning his attention to the other classroom. Rin stood there boiling not just because of Yukio's lies but also because of Mephisto obviously is manipulating him. He felt the words of his new found mentor creep into his mind. He tried to fight them off but in the end the words destroyed his mind.

Mephisto continued, as Rin slipped on his mask "Now that this little lesson is complete, huh?"

A dotted line silhouette of Rin flashed where he used to stand and a confused expression emanated from Mephisto. He heard stomps in the hall and the door in the next room fling open. Before his other human ward could react, the demon planted his fist into him effectively knocking him out. Mephisto sat on his desk and sighed as goblins began to rain down on his little pages.

Suddenly, his eyes widened as the little demons stopped and stared at Rin. They quivered in fear and rose back up to their nests. Mephisto sat back hands lacing together. He talked to himself aloud. "Marvelous, I've never seen such great control over lower class demon, especially ones sent into such frenzy not since father. He truly is his carbon copy."

Then, he saw Rin's little assault on Izumo and giggled, "Well that will make guard duty a little awkward!"

After Izumo heard Rin's words, she stepped back blushing. A hard slap resounded on his mask but the demon pheromones on Rin made him care not. The slap did wake him up a bit and he stood back suddenly realizing his surroundings. He heard Yukio's half-conscious groans and he looked back at him in sudden urgency. Bon sat up and shouted, "What the Hell?"

Rin ignored the shout and ran out the door and down the hall way aimlessly. Bon stood there again terribly confused, "Wha-what the fuck just happened!?"

Five minutes later, the pages managed to nurse their teacher back to consciousness. As Yukio began to come to, he suddenly snapped up. "What the hell just happened!?"

"You got knocked the fuck out!" Renzou Shima shouted and the shyly stated afterward while rubbing the back of his head, "Just kidding, Sensei, but no joke this dude in a crazy mask and clothes just punched you and summoned a pack of goblins to scare us."

Yukio looked up shocked. He stood up and looked at some wounds on his students. Sighing he said, "All those injured come here and I'll treat you." He took out some gauzes and anti-bacterial creams. He ushered them over but a broken vial of blood on the floor caught his gaze. He strolled over and looked at it.

"No," He said, "This is what summoned the goblins. Where did they go anyway? I want the full story."

The pages exchanged looks and delivered their whole accounts. Izumo left out the words he said to her but included his actions towards her. Yukio slowly digested the information and picked apart any evidence. He leaned on his desk and liberated the class from their confusion, "It seems that I was just attacked by a high class humanoid demon. He must be ridiculously powerful to command demons like that and Izumo," Yukio gave a cold stare to hide his embarrassment, "It seems you have managed to … enthrall that demon."

The class turned to Izumo shocked but she gritted her teeth and said, "What does that mean?"

"Well sometimes a demon will become possessive over another demon when it is imprinted on yet it usually takes several hours to even kick in."

"Wait, I'm not even a demon." Izumo shouted.

"I'm not sure, you yourself might know the answer to that but I must ask have you come into contact with anyone new today." Yukio questioned.

The flash of Rin's face popped up in her mind but she waved it off. He was Yukio's brother meaning he would be noticed but wait they don't see each other anymore. Her mind held a picture of Rin smiling and she thought, 'No it's impossible.' She looked up and said, "It was the first day of school. It could have been anyone"

Now walking out a door which leads to the outside world, Rin and Mephisto discussed current events. Mephisto jeered at him, "So let me tell you about the demon birds and the demon bees. You see when a daddy demon finds the scent of mommy demon attractive he marks her sent into his brain. He becomes like a knight in shining armor for the other demon. His life no longer matters when she is around."

"What are you even talking about clown" Rin grunted.

"I'm talking about you, Okumura-kun." Mephisto now said a bit annoyed, "You've managed to be the only direct child of Satan to ever go through a demonic imprint. Do you understand? You and Miss Kamiki are now linked. Mostly on your part though. You see now every other thought in your dumb little head will be about her."

Rin blushed, "Wait Izumo! N-no way."

"Shush, boy, you adolescent demon horniness was already well portrayed in that classroom. This has effectively thrown a wrench in my future plans for you." Mephisto whined playfully.

"What do you mean?"

"We are powerful demons and as such anything we mark will have a certain stigma to them. This stigma will draw demons in and put them in a frenzy." Mephisto continued.

"So basically that means…" Rin said tears forming.

"Yes," Mephisto answers, "Now your job of protecting your new found fiancée has gotten a lot harder."

As those words pierced him, Rin collapsed depressingly. Mephisto added, "Also, If Satan discovers her he might react unexpectedly. You see he is uncontrollable sorta like you. He might take you both and set up a marriage with extra blood, oooor slaughter you both."

Rin gulped. The two exchanged looks perhaps an unspoken bond between brothers although one was unaware. Mephisto sighed, "Whatever let's just see this result. It seems this rogue ronin anime has turned to an action-romance type."

Rin stretched. Now the chains on his jeans were jingling. He grunted, "Yeah I just found out I'm eternally linked to a girl I met eight hours ago. I'm just going to work at the girl's dorm."

Three hours later, Izumo was eating dinner at her dorm. The tamer had decided to catch a late dinner she quickly ordered a top class dinner from the more expensive kitchens. Her mind wondered to the masked demon. She couldn't help but feel an attraction to him. It was mostly his scent. The smell of smoke overpowered her sense in memory. She walked over to where food was picked up. She tried to forget the scent but it only got stronger for some reason. The smell now felt more real.

As she clasped her hand on her tray, which was pushed by a cook from a window leading to the kitchen, she couldn't help herself and let slip a curse, "God damn it!"

"Are you okay, Eyebrows" Rin asked worriedly. Izumo looked up at the cook that fixed her food. The girl looked over and saw Rin with a cook's wardrobe looking up with a concerned face.

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