Due to all your input Shiemi remains a girl. Hope you like this.

And thank you. I crossed 100 reviews. First milestone crossed. I'm so happy I cried. My family thought I went nuts.

And now our govt had decided to go nuts. We're having a two months long finals. TWO MONTHS. THE HORROR. They begin on 7 march and finish on 28 April. My two months are ruined.

Summary: Six years old Rin found a demon summoning paper and books in Shiro's room. She accidently called out a king of hell while playing with it. Poor child is now stuck with a bunch of overgrown childish hell king popping up at odd times. What's more? They think she is their youngest sister and want to take her home. (smart fem Rin, protective brothers)

Yukio liked teaching. Yeah, it was tough and sometimes gambled on his grades but then again he liked this because it gave him a sense of fulfilment. Even more so now that his twin Rin had joined the cram school. He could harm away, ah, he meant warn away, right warn away anyone who might be a threat to her sister.

But right now he was in a bind. As a teacher it was wrong to hit another one, no matter how they looked like. That's why he was trying to contain his desire to main the little shit who thought that he could paly coy with his sister. Just what had Mephisto been thinking when he had introduced this little child.

For the past one hour the red haired child had clung to his sister as a boyfriend does to his girlfriend. He really did not like this. Did this little child had a crush on his sister? It was no allowed.

"Ibilis-san, kindly let of Rin"

He had to be polite even if he would like nothing more to rip the child in shrewd but his job as a teacher was to guide his students and child or not he could not set up this an example.

"I won't. Rin's mine"

Forget decorum. If that little shit did not let of his sister this instant the heads would roll and he would be the one pushing the trigger.

But maybe he could wait. His thoughts took this turn as he saw the little boy shoot a glare to a boy who was eying his sister. Maybe he could allow this nascence to hand around his sister a little longer of it foiled others plans with his sister and surely his sister won't go for a child right? And it was a child, how bad could he be?

He quickly shot his thoughts down as he saw his sister smack the redheads' hand which was trying to creep a place it shouldn't be.

Yeah, it royally fuckingly did hate his job today.

...

Rin's first day was a mess. Sure it had gone almost alright at first but she was in pain, had seen Shima, who did not want to do anything with her with the looks of things, having Ibilis as her instructor, Ibilis being Ibilis and did she mention plain Ibilis and Yukio's strange mood.

Yeah, her first day was a mess. But this was a new day and thankfully they did not had school today. She had made a quick run to the stood and somehow Ibilis had found her. Where was he living anyway, with Mephisto? Did he even had anything to eat because god knew Mephisto lived off instant Ramen and take-outs'.

So she being the kind sister she was had invited him for dinner. Yukio wad not impressed but he would compromise.

Anyway, after dinner Yukio had received a mission and she was so bored that she had begged Yukio to take her with him. He would naturally have refused if not for Ibilis egging him. She never knew Yukio was so sensitive. And what did Ibilis meant by alone time with Rin exactly? It had irked Yukio too much. Just what was he thinking she did not even know.

But the point was that the were now here on the mission with Yukio who had just entered the exorcist supply shop and she was here with Ibilis.

Key word being was, for as soon as they had arrived here and Yukio had entered the shop Ibilis had take off and she needed to find him.

"Demon"

The voice sounded scared and for a second she was afraid if Ibilis and hurt a human or not, do she decided to follow it and it turned out it was Ibilis. Yukio meanwhile had also joined them.

"Oi, I'm half demon. Show some respect"

Did that idiot have to sprout this non-sense? And wait, half demon? When was this agreed upon? From the corner of her eyes she saw Yukio not surprised at all. Was this something they had added in introduction? She should have paled attention to it damn it. She had no idea what cover Ibilis was using.

"Shimei, are you OK?"

He younger brother asked the girl. Did he know her? How? Was she someone important to him?

"Yuki-Chan"

Yuki-Chan? Were they both...dating? Yukio had not even told her. He was allowed to date but not her? What kind of justice was this. Yukio was gonna get an earful. But first thing was to resolve the mess Ibilis made.

"I'm sorry. He's my exorcist teacher, but sometimes he just acts his age"

Oh what would she not give for Ibilis to act his age for once but nooooo. He just had to act like a child all the time. At least now he had an excuse. Yukio had meanwhile come over close to her and stood right next to her.

"Shimei, let me introduce you. This is my elder twin Rin, Rin Shimei my...friend you could say"

She saw the girl blush, just what had she taken their relationship as? Dating?. Ah, so that's how it was. Friend. Did he take her for a fool? His brothers had other friends but non called him Yuki. Then she realised that she was being stared at.

"You're cute"

It was not the first time someone had called her cute but to be called so abruptly and in front of her brothers left her flushed. She saw Ibilis's eyes narrow and next thing she knew was that he was clinching her waist too tightly.

"Mine"

Just what was her brother up to? Yukio was just an inch away from shooting him.

...

When Ibilis had started this child possessive act he had thought that it would be fun and will cure of his boredom. If he could annoy Mephisto then it was a bonus.

Yukio was also a fun target. Not as fun as Amaimon or Egyn buy fun non the less. As far as he was concerned he was non important family, might as well be unrelated to them all. But fun to bait all the same.

Also, Rin was a girl. Sister or not ot was always fun to flirt with a girl. More so if she had an overprotective brother like Yukio.

And when he had baited Yukio to come on this mission he never agreed him to agree but here he was with them. And now this girl, this blond haired idiot who was staring at his sister and called her cute.

He did not like it. Did not like her at all. Rin was theirs, he was not giving her up to anyone. Girl or not.

Earlier he had thought that they only have to worry about boys, but now looks like girls were added too. All of the others had to be informed of this development.

He could say he was guilty to seek pleasure when the girl and and her mother had that falling out. He was a demon, kinda in the code. But he was not happy when Rin took after her.

Yukio decided to follow her, and he would have too of the call he had to make was no so important. Who first, who first.

Azazel

"What's wrong? Are you hurt? Is Rin hurt? Are you in danger? Gambling gone wrong?"

Just what was he taken to be? A walking disaster?

"No one is hurt but soon someone will be. And I'm not a bad gambler you hear. But right now we have more important things to worry about. You see earlier-"

And that was long call. Halfway through the call Azazel had gone quiet as a mouse and he had no idea what was going through that mind of his. Then the phone line had gone dead, that bastard had hung up on him. He'll have to leave the rest to Azazel.

He heard the gun shots and hurried. If something happened to Rin then he was a goner.

He reached in time to see that blond haired girl in the grasp of a weird plant like demon. He would have assisted but then Yukio shot her. His respect for him went up. Now that's how you should roll. The demon disappeared too.

It would have been a happy occasion if not for Rin catching the girl in her arms and laying her down. It was all wrong.

He had to do something.

He saw that girl gaining consciousness and looking up at Rin with those eyes full of admiration. It was dangerous. Admiration could quickly change into obsession and he had to stop it. He jumped on top of Shimei and hugged Rin who was standing just in front of her.

"Mine damnit. M.I.N.E.,I'm not sharing"

Now he had to get her out. Unluckily for him Yukio decided they stay till all this mess was over once again.

He opted to stay out and dragged Rin out too. Thankfully it did not take long. Now they could go back.

The next day he got the shock of his life seeing the same girl in the school. He could not take this much pressure. He had to call in reinforcements.

To Mephisto.

And there it's all done. Hope you like it.

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