Hi there! This is my second story in English and I hope it will not be too bad ^^"
I've been falling in love with Yukio and Rin later on so I decided to write something about them. This fanfic is a reflection about their bound.

The title is Latin and it means " A Joke of the Fate" even if "iocum" means both "game" and "joke". I meant with that the fact that the twins have to "play" their match against Satan and at the same time they have to deal with the fact of being half demons and because of that they may never have a relly happy life even after winning their battle. This is the "bad joke" of destiny.

Every comment and review is welcome! I hope you will like it!

Disclaimer: I don't own Ao no Exorcist or its characters!

Iocum Fati

It had snowed a lot during the night and now under a pale sky the landscape spread white, kissed by the weak ray of the winter sun that made ice crystals that coated it shine. The snow lay thick on the ground and muffled the sounds creating a blanket of silence that seemed to envelop the still asleep world in a protective embrace, while the morning air was made even brisker by the bitter cold.

Leaning on the windowsill of the room he shared with his brother, Yukio admired spellbound the view, his mind lost in his childhood memories when , during winter he and Rin woke up at dawn just to throw themselves in that white sea and then they spent whole hours rolling around on it, careless of the frost, while Shiro was left to watch them smiling, seated on the steps of the church. Their cheerful laughter rang out in the silence of the courtyard greeting the light that rose from behind the leaden sky, while they were busy having a snowball fighting or trying their hands at the construction of some strange snowman. They were good times, so happy and carefree, so innocent. Though the secret that surrounded his and his twin's birth had come to his knowledge too soon, at least until their foster father had been alive, he sensed that grave awareness as it was something far, detached from reality he lived in, and, even while training to become an exorcist, he had managed to coexist with it without perceiving his real burden.

Then, suddenly, that apparent equilibrium had broken and the events had degenerated without warning, forcing him to clash violently with the concrete. Seeing the typical demonic features on Rin's body and being kneeling before the Shiro's grave all that before had been only vague and indefinite idea had now tuned before his dumbfounded eyes into hard fact and he had had no choice but to wearily take stock of things. Time had passed since that day, but, although he had got through the initial state of shock, he still hadn't managed to fully adapt to his new situation.

Yukio shifted with a sigh his gaze from the snowy landscape to the bed where his brother was lying still asleep, giving up those gloomy thoughts. He didn't want to get lost in those thoughts again, not that day. The only thing he wanted at the moment was to spend a good day with his twin. A sad smile spread on his lips as he got up and went sit on his brother's bed. Despite everything, the story had a bright side: after the initial conflicts, he and Rin were now close to each other as they were in their childhood, and maybe even more without secrets between them. Sometimes, in moments of anger, Rin accused Yukio of not being able to understand him because he was the only one who had inherited Satan's power and yelled that therefore Yukio had no right to blame him for his decisions or to make claims towards him, but eventually the fight was overcome and quickly forgotten with a hug or a smile. Yukio preferred not answering those charges, although he would have too often wanted to scream that he himself still remained a son of the prince of demons, that it didn't matter if he had the appearance of a human being because the feeling that one day his powers would awaken too constantly torment him, that he also suffered because of their half blood nature but he did not show in order not to cause further distress to his brother. He was sure that Rin knew how he felt and it was for this that they always make peace in the end. And then, even if he hated to discuss with his twin, those fights were for them both a chance to vent their frustrations and to share their mutual uneasiness. That nonstop war ended to do anything but making them closer to each other.

The young exorcist reached out a hand and gently stroked Rin's ruffled hair, enjoying the feeling of softness to the touch. The other half demon let out an annoyed moan and sank his face into the pillow for a moment before looking up to his twin, still half asleep.

"Good morning, Nii-san," the younger greeted with a smile, withdrawing his hand. "Did you have a good night?"

"Yeah, sort of" he muttered, yawning and looking around the clock. "But, Yukio, what time is it?".

"About half past six, Nii-san. I didn't mean to wake you up, I'm sorry" the reply was. "If you want you can go back to sleep."

"Six? It's early!" Rin groaned back to sink my face into the pillow with a snort. "What the hell are you doing awake at this hour? You're crazy! We don't have lessons 'cause there are school holidays and you wake up at dawn!"

"I had to finish a couple of reports for Mephisto by this afternoon, and so I had to get up. Later I'll hand them in. You know that with my work as an exorcist I have not only school to worry about" Yukio explained pointing at the sheets neatly stacked on the desk. "And then it snowed last night, Nii-san! The landscape is really beautiful and I didn't want to miss the sunrise. I've always loved the snow."

"Me too!" the half demon exclaimed, livening up a little and sitting down so he could see a glimpse of the candid landscape outside of the window. "We had a lot of fun when we were children, do you remember? We played until the cold got the better of us and our father forced us to go back in because we were shaking like leaves... ". An almost a nostalgic smile opened on his face. "They were good times...You know what we could do? Since I'm awake and there's no way I'm going back to sleep, we could go out to enjoy the snow!"

"I'd love to, Nii-san. It's been a while since the last time we spent a day out together. And then Christmas and our birthdays are close, so it may be also a good opportunity to buy a gift for us" the other agreed happily, standing up. "Do go and take a shower unit while I make breakfast."

Rin nodded vigorously drawing the sheets away and putting his bare feet on the cold floor. "Yukio?" he called back. "What if we eat outside? Come on, there's this bar in the town centre where they make brioches that terrific!" he suggested, his eyes sparkling at the thought of warm croissants. "Please!"

"As you wish, Nii-san. So while I wait for you I'll take the chance to review those documents. Take your time, we are not in a hurry for once" Yukio smiled, shaking his head amused. Sometimes his brother acted like a child, but he could not blame him. The fact that Rin managed to be so carefree despite their situation made him more calm in turn and made him more determined to protect his twin from everything and everyone. They were those moments that gave him the strength to move forward and face the reality, to fight in order to see again smile on Rin's lips and to give back a normal life to both. He gently ruffled his brother's hair, earning this way a dirty look, then he went and sat at his desk, grabbing one of the sheets and immersing himself in reading.

Rin stared at him for a moment, then he shook his head and hastened to slip into the bathroom. His brother worked too hard, had no doubts about it. He was always carrying out this or that task, or away for a mission or busy compiling a report on God knew what. And, when it wasn't his job as an exorcist that kept him busy, he was bent over books to study. Rin would have die after less than a week in his place, but Yukio seemed to enjoy burdening himself with commitments, as if his life depended on keeping himself constantly occupied. He never refused an assignment, unless he was already busy with something more important. The older twin had wondered time after time where Yukio found the energy to look after the endless queue of its commitments without drowning among them. You had to be real masochist to desire something like that, there was no other explanation. Moreover, not satisfied with that, Yukio also claimed he had the duty to look after him almost around the clock, treating him as if he wasn't able to stay alone for more than few hours without making trouble or get into it. That was what he understood less and hated more in all the craze of his twin.

Rin slipped under hot water, snorting annoyed. It was true, he had often proved himself to be unreliable and impulsive, but he had always acted for the good of the people he loved, Yukio first of all. That protective and almost distrustful attitude bothered him a lot, especially considering the fact that when they were kids he was the one who used to console his twin and to defend him from the world. He could not count the times he came home full of scratches and bruises after a fight to have defended him. But he had never complained and he had always endured the pain almost with pride because he knew that he was doing it for the person he cared the most in the world.

But now things were very different and he couldn't stand that exchange of the roles. It gave him a anguished sense of frustration. Yukio was now the one who worried about and who always claimed to take care of both, trying to carry all the problems that showed up by himself and to keep them away from Rin, though he often risked to suffocate under their weight. Rin knew that his brother behaved that way because he loved him, but he couldn't tolerate that someone was hurt because of him. In the end he was always the problem, he and his demonic nature.

He clench his fists raising his face so that the hot jet could pour above it. All the people around him ended up paying a price too high and that they didn't deserve just because they were stubborn about staying at his side despite all the risks it entailed. His mother had died giving birth to him, Shiro had sacrificed his life to protect him from Satan and Yukio had first renounced his dreams and then to his happiness to continue the mission of their guardian. Seeing the burns on his brother's skin, the same ones that he and his damned flames had caused him, made him feel bad more than anything else, perhaps even more than being knelt in front his adoptive father's grave.

He let out a sigh, passing a hand absently on the tiles of the shower. How many times he had tried to explain that pigheaded that he didn't need all that protection, that he could look after himself. But Yukio had always refused to listen and continued to take all the responsibilities, even when it wasn't needed. And Rin hated him for that, as much as Yukio had to hate him because of his nature. Yet he couldn't help but feel a comforting pleasure in seeing that in the world there was someone who cared so much about him. He couldn't avoid looking almost desperately for his brother's support and he could not describe his relief in knowing that he was always at his side. Because without him, although Rin would never admit it even to himself, he would be lost.

A soft knock interrupted his thoughts, bringing him back to reality. Rin pulled himself together, leant out from behind the sliding door of the shower. "Yes?" he asked.

Yukio's head appeared from the entrance of the bathroom. "I just wanted to know if everything was okay, Nii-san," he said with a smirk. "It's half a hour the water is flowing...I thought you have fallen asleep in the shower."

"You're a bundle of fun!" the half demon mumbled shooting a dirty look to his twin to hide his embarrassment. Half an hour? He was so absorbed in his thoughts that he had lost track of time. "You told me to take it easy and I did! And besides you have waken me at dawn after yesterday we went to bed late, so you can't expect me to be fully awake! I'm not a computer like you who need just go in standby for a couple of hours to be fully charged! And by the way, didn't you have some work to do?"

"I finished. If you were tired you could have stayed in bed, Nii-san. I told you, I didn't want to wake you up" the exorcist apologized raising his hands. "You don't have to come out with me if you don't want. Maybe you already had other plans for today ... "

"No, no, not it's not that! I really want to spend the day with you." the older twin hastened to say, feeling uncomfortable. "I didn't mean to get smart. It's just ... I was thinking and I haven't realized I had spent so much time in the shower. Give me ten minutes and I'm out!"

Yukio smiled. "Don't worry, Nii-san. I just wanted to make sure that you are not doing this against your will," he explained looking away embarrassed. "I mean, now you have finally managed to make friends and everything else...It would not surprise me if I prefered to go out with them than with me. Maybe you wanted to see Shiemi."

Rin dropped his gaze in turn feeling a little heat invading his cheeks. "I can see them another day, even Shiemi. And then we hadn't planned anything for today! "he assured slipping back under the water. That idiot never changed, he and his damned hobbyhorses. Was it possible that even being a genius he didn't realize that he was pleased to spend time with his brother? "Stop being paranoid! I said I'm going to spend the day with you and this means I want to, Ok? Get out, so I can finish here. I'm starting to get hungry by the way."

"Thank you, Nii-san" the younger twin murmured to himself. Then in a louder voice: "Then let's do like that: since I'm finished with the reports, I'm going now to Mephisto's so you'll have all the time to prepare yourself and then we'll go and have breakfast."

His brother mumbled something that sounded a "Ok, but hurry up" and Yukio exited the room after shooting one last glance at the opaque and clouded glass of the shower door. He was glad to hear those words from his brother's the mouth because Rin showed his affection through that kind of attitude. The eldest almost never made explicit declarations, he found them too embarrassing, but he could always make him understand his own way that he cared a lot about him.

He sighed, running a hand through his hair and heading out of the apartment, the documents tightly held to his breast. He had to hurry up so they could go out and enjoy their day together.