Info: This story starts around the True Cross Academy Festival arc and in this AU, Shima is not a spy. This story was inspired by Tokyo Ghoul, in which there are ghouls (similar to demons), that mutate through repeated cannibalization. I will be bastardizing this concept slightly and I hope you enjoy it.

Disclaimer: I don't own BE/ANE or any of its characters.

Chapter one,

The Kakuja Effect

The changes that Rin experienced were subtle in the beginning, and by the time that he had noticed that something may be wrong, it was already too late.

At first, it was just his sense of smell that had changed. Rin just assumed that when he became a demon that his nose had become overly sensitive to certain smells, which wasn't exactly wrong. But when the smell of freshly cooked Sukiyaka, his favorite meal, had made him grow nauseated instead of hungry, he began to grow disinterested with cooking. Most meals smelled wrong to him, like they had been prepared with rancid meat on a hot summer's day.

After his sense of smell changed, his sense of tasted followed soon after. Regardless of what he ate, or what he cooked, everything that he ate tasted like it was on the verge of spoiling. Even the food that Shiemi made him, which normally tasted like herbs, made him sick within minutes of consuming it. It got so bad that even just looking at food made him sick to his stomach.

The most bizarre change though, in his own opinion, was his attraction to people. His romantic attraction towards people had not changed, but he found himself growing hungry when he was around large groups of people. He couldn't help but go to areas crowded with people, the alluring smell of them was maddening. To him, they smelled sweet like freshly baked sticky buns.

The final change was his constant and insatiable hunger. It was the kind of hunger that left you awake at night, begging for any sort of relief. The hunger that he felt was always in the forefront of his mind, but no matter what he ate, it would leave him feeling sick and he would end up vomiting the contents of his stomach, leaving him hungrier than before. The painful, aching sensation of his empty stomach was growing worse and worse by the hour.

One day, Yukio had left the dorm room earlier in the morning than usual. He had mentioned something about a low-level demon that was running rampant on the academies campus and causing trouble for the exorcists. Yukio tried to explain to Rin what was going on, but when he glanced over to Rin's side of the room, he appeared to be fast asleep.

Yukio smiled to himself as he left the room and thought, 'Some things never change.'

Rin waited in his bed quietly and completely motionless until he heard the door to their dorm room click close. When he heard the latch click, he unintentionally let out a quiet whimper. Rin hadn't been sleeping at all, in fact, he hadn't slept in days. To keep himself from crying out, he had bitten down on his own fist so hard that it drew blood, coating his lips and tongue in sweet tasting blood.

Warm, salty tears poured down his face. God damnit, he was absolutely starving. What the hell was wrong with him? No matter what he ate to try and satiate his hunger, it always made him sick as a dog. Rin raked a hand anxiously through his hair, he had no idea what the hell was going on or what to do about it.

"Please stop…" He cried out uselessly, "Someone please, I don't know what to do…"

'Yukio, he would know what to do, right? He is the smart one after all.' Rin thought desperately. 'No! Don't cause him any more trouble, you've caused him enough issues as it is.'

Shakily, Rin pushed himself upright into a seated position, and pulled his knees close to his chest. He wiped his bloody hand off on his pants, not caring that it might stain. He then rested his head on his knees and sat there in silence for a long while, the grumbling of his stomach occasionally breaking the silence. He nearly nodded off until a particularly strong hunger pang roused him again. He looked at the clock on the desk and a jolt of shock ran through him, an hour had already passed since Yukio had left, even though it felt like he was there mere minutes ago.

Thrusting himself up and out of his bed, he rushed to his feet, only for his vision to begin to blacken. He had stood up way too quickly, gripping the desk to stabilize himself, he waited for his vision to return. The malnutrition and dizziness that came with starving had made him extremely lightheaded, and his legs shook with fatigue. He waited there for a moment longer, trying to pull himself together. He couldn't let anyone know; he could not look weak in front of them. They would probably think that this is what he deserved for being the son of Satan.

In the back of Rin's mind, he knew that that was not true. His friends would stand by his side and help him if he asked for it, but his thoughts, twisted from ravenous hunger convinced him otherwise. They coaxed him into believing that this was all somehow his fault.

"Please just make it through today." Rin begged himself.

-~x~-

Yukio liked to think that he was a patient person by nature, and that he had the capacity to be understanding of others, especially when it came to his brother, Rin. But sometimes, Rin really, really seemed to like to test his limits. Yukio had patiently postponed the beginning of his class for five minutes to try to give Rin some time to arrive, but five minutes turned into ten. And then ten turned into fifteen. After twenty minutes of waiting, it had become abundantly clear that Rin had every intention of skipping class, and zero intention to join his classmates. Even if Yukio tried his best, he could not stop the world for his brother.

He gingerly massaged his temples, just barely fending off an impending headache that was beginning to build up behind his eyes. It would take a little more than a tardy student to break his composure, even if that student was his own brother.

Yukio let out a short huff and then said, "I apologize for starting late, I was waiting for everyone to show up. Now don't worry, I won't make you stay any longer than usual to make up for lost time. If you could pass these out, Shiemi, that would be great…" He handed her a small stack of papers to hand out to the other students.

It was a relatively boring lecture, if he was being honest with himself, on how to properly clean Naberious inflicted wounds, and how to stop them from becoming infected and putrefying. He was in the middle of going over a list of purifying herbs that can be used to help treat and reduce the swelling of Naberious wounds when the door to the classroom creaked open.

Without looking up from his own list, Yukio simply stated, "Rin, please take a seat next to Miss Moriyama. Shiemi, could you please fill him in on what we just went over-" He glanced up at Rin and froze.

Rin looked to be a complete and utter mess. Aside from being disheveled and haphazardly dressed, his eyes were red and puffy as though he had just spent the greater part of the last hour crying. His eyes, which were normally so full of joy, were void of their normally fiery passion. He had a fake smile plastered on his face and his voice cracked when he spoke.

"Sorry I'm late!" Rin said with forced cheeriness, "I promise that it won't happen again, hopefully."

Before Yukio could collect his thoughts, Rin began to shuffle over towards his desk, and he slumped into his chair. He tossed his bag half-heartedly onto the ground and stared at the floor. The whole classroom had gone silent. Yukio walked over to Rin's desk and leaned over, whispering so that only Rin could hear him, "Rin, what's wrong? Did something happen?"

"There's nothin' wrong." Rin responded too quickly, he then added, "It's nothing. I promise."

Yukio gave Rin a pointed look that said 'I-know-that-you're-lying-and-we-need-to-speak-after-class.' Rin broke eye contact and went back to staring at the floor, he really didn't want to talk to anyone right now.

"Right," Yukio started, clearing his throat, "as I was saying…"

He set a copy of the list of herbs that they were going over onto Rin's desk and continued his lecture. Throughout the lecture, he would sneak glances over at Rin. Shiemi was trying to explain to Rin on what he had missed, but Rin just continued to stare at the floor, clearly not interested. He just nodded and said, 'Really?' whenever Shiemi paused. Yukio's eyes wandered around the classroom and he caught Bon's eyes, Bon's troubled expression mirrored his own. Something was definitely wrong.

At the end of the class, Rin tried to leave quickly so that he wouldn't have to talk to Yukio, but Yukio grabbed him by the elbow and pulled him back inside the classroom, waiting for all of the other students to leave before he asked, "Rin, what's going on? What happened? Are you hurt?"

"It's nothing, really."

"Why are you lying to me? You can tell me anythi-"

"I said that nothing is wrong!" Rin snapped back at Yukio. He wrenched his elbow from Yukio's grip and walked swiftly away from the classroom.

Yukio just stood there in stunned silence. His mind was working at a mile a minute trying to piece together what had just happened. He walked around the corner to try and catch up to Rin, but his brother was gone. He had no other option than to try and ask Rin later tonight at the dorm room, a place where they could talk in private.

The only issue with that was that Rin didn't return to the dormitory that night.

He didn't return for two more years.