A while back, nearing two years ago, he had been on a mission to a remote part of Japan. He had been tasked to investigate a suspicious gathering of magecraft practitioners that had been popping up. Normally, a magus was suspicious by default, as it was more or less policy to keep secrets regarding one's magecraft.

The Shingon Tachikawa Eiten School was somehow even more so.

It had been on the Clock Tower's radar for a while now, having been brought to attention after some sort of tantric ritual that had been publicized as some sort of scandal to the public eye. Even then, it wasn't until Waver Velvet of all people caught wind of it and brought it to wider scrutiny.

Enough that Senior Enforcer Emiya had been tasked to infiltrate it.

That was easier said than done, seeing as they apparently didn't have any easy way to contact them. And when he did find a way, they didn't even reply. So, he had made the executive decision of just heading to their temple in the Japanese countryside.

He had seen a lot of things in his time as an Enforcer. Shirou thought that he wouldn't be as surprised to find just about anything by then.

He was wrong.

As if the World was laughing at him, he bore witness to the aftermath of depravity. A scene that could only be described as the last vestiges of a madness. Even to this day, he wasn't entirely sure as to what had transpired up in those mountains. All he knew was that the various men and women were all dead, naked, covered in every single human fluid, and had the look of utmost bliss on their still faces.

All in front of a portrait of a woman none at the Clock Tower could identify.

A cult, they had concluded, though not without some hesitation. The signs were all there for religious worship, but without a living person to confirm it, it could have been just about anything.

Still, the scene now in front of him as he walked into town was starting to look more and more devolving into that madness, even if it was somewhat less so.

Shirou walked into the town, seeing the destruction that had happened in the aftermath of the earthshaking. Wooden buildings as they were, more were collapsed than not. With a grimace, he could spot more than a few bodies underneath, having been caught trying to get outside.

Still, he couldn't see anyone as he jogged through the streets. Reinforcing his ears, he scanned around him, finally hearing noise nearing further into town. He picked up the pace. Soon enough, he could see what was happening, right in the town center.

A priest of some sort, clad in fine cloth, was standing at the front of a crowd. The man gestured wildly to a group of what Shirou assumed to be slaves with their faces, much to the magus' disgust. The crowd was very obviously enraptured by whatever he was saying, and every other moment the priest spoke, he was met by shouts of approval.

"Look, brothers and sisters, and see! The Gods' wrath has struck this land, and we have no one but them to blame! These monsters, the Gods have already seen fit to bless us the means to defend ourselves against, and yet, how do we repay them? By letting those same monsters live among us? I say, no more!"

The priest ripped off the covering on each one, going as roughly as possible it seemed. Muffled screams from the slaves as Shirou watched. He couldn't tear his eyes away as the mob jeered at the wolf men. Their hands and feet bound, mouths gagged, and yet their eyes remained for them to take it all in.

Fear. Anger. Defiance. Despair. Hatred. Acceptance. Hunger. Each one of them held some strong feeling, in one way or another.

"Come, all you who listen! Our sins have already accrued a debt, one that can only be paid in blood!" The man grabbed the closest wolf man, who could only give out a small whine in response. They were thrown onto the ground, before the priest started beating down on him.

What followed was chaos. A dozen or two of the crowd leapt forward with yells of approval from the rest, and followed the priest's example.

That was the last straw.

The fury that he had been keeping in check, the anger that he had waited for so long to do something, and the hot white rage at the men and women beating the oppressed-

The sword at his waist was ripped out with a shout. Had it been any other instance, eyes would have been on him the moment he did that, or maybe when he charged into the fray like a madman. Now though, even as Shirou made it to the front of the mob, all eyes were on one thing.

The broken shackles on one of the demi-humans.

Just one hit was all it took. Very clearly, the crowd were avoiding the restraints even in their beatings. The demi-humans would cover their faces with their shackled wrists, only for the mob to hesitate when they did so. All this, Shirou could see as a passenger of his own, moving body.

Up until a single slip up. Someone had kicked forward, and the wolf man he had been kicking threw up his wrists at the last second. The heavy foot slammed against the shackle, going forward and into the slave's face. Nobody moved for a good second. A new tinge of fear, palpable even for the most violent of the mob.

"IT'S FREE! RUN!" Shirou didn't know who shouted, but it kickstarted a flurry of panic that quickly left Shirou alone with the now unmoving wolf man. The townsfolk ran all over the place, into each still existing building that they could, and he didn't need to Reinforce his ears to hear the slam of locks on their doors.

Turning to the freed demi-human, he tentatively called out, "Are you alright there?"

He didn't get an answer. Not an answer he expected.

The wolf man roared out, the sound even managing to shake Shirou out of the confusion he found himself in. The danger in front of him was quickly assessed, and he held out his sword in front of him just as the demi-human threw themselves forward.

Not at Shirou, to his horror.

It would have been fine had they gone after Shirou. The magus could defend himself. It would have been fine if they went after the one that had beaten them up. Shirou could intercept before they went too far.

Shirou could not defend the ones right next to the wolf man, the same demi-humans that had been beaten right alongside them. He could only watch as the freed demi-human leapt at them. Mouth first.

Strips of flesh were ripped from the first, going noisily down the wolf man's throat before Shirou could get over his shock. The demi-human was relentless, tearing their victim apart limb by limb, and swallowing said limbs, bone and all.

It was less than five seconds, and already, the demi-human captive was dead, and the cannibal reared their head to the next one.

In those five seconds, Shirou had remained frozen. On the sixth, he got his bearings and dashed forward with Spartacus' blade. The wolf man whirled around, catching the blade with their now freed claws. With surprising strength in spite of the malnourished form, Shirou was held in place.

Shirou didn't hesitate to punch against the cannibal's chest with a Reinforced fist. He felt several bones break under the punch, even as the wolf man was pushed back. Shirou once again assumed a defensive stance, only to balk when the demi-human ignored him, despite the obvious danger he posed, to go for the other wolf men.

Thankfully, Shirou was more prepared this time. The Enforcer rocketed forward, placing himself in between. He bodily lifted up the demi-human, before slamming him on the ground. In the brief moment of pause where his opponent was stunned, Shirou whipped around and swiftly cut through the bindings that each one had.

"Your chains have been cast aside. Live freely, my friends." All the townsfolk were holed up inside their homes. They wouldn't know that he had been the one to free them. All he'd have to do was lie to them, say that the demi-humans had freed themselves after the first one, and his cover would be secure.

He felt the satisfaction of a job well done from the blade, echoing his own thoughts.

Shirou shelved it as he drew up his blade once more, against the now-rising cannibal, "I shall cover your escape. Flee now, and kee-"

Squelch.

Shirou snapped his head towards the others.

Maddened hunger.

Claws on flesh.

Each one of the demi-humans he'd freed jumped towards the closest to them, and, like the first one, fell upon each other in a feeding frenzy. Even as one was biting into another, none of them cared. Even as they lost limbs, bled almost bone dry, they continued to eat.

Eyeballs flew as one of them was hit hard enough in the head, only for the eyeless demi-human to bite into the neck of their assailant. One that was the size of a child, their legs lost, was crawling relentlessly on the ground, dragging themselves to nibble on the ankles of the taller ones.

The sword almost fell from his hand.

Animalistic grunts were all that could be heard as they ignored Shirou, opting to continue feeding on each other. He was similarly ignored by his opponent, who'd opted instead to join the entire horror show.

He couldn't tear his eyes away.

Eventually, all that was left was the very first freed slave. The demi-human sat down on the ground, staring blankly into the air. Gone was the hunger that had been present this entire time. Left, was the hollow shell of a broken wolf man, cradling the remains of a smaller individual. The same individual he had feasted on not moments before.

"...Why?" Shirou whispered into the stifling silence. He couldn't think of a good reason, not one, for the insanity he had witnessed.

"...I was hungry, and they were weak."

He didn't expect a reply.

"What?" He couldn't help the indignant tone from rising, "All that, because you were hungry?"

Barking laughter, the sound grating to the ears, "A human like you would never understand." The wolf man bared his neck to Shirou, looking down to the ground, "Do me a favor, will you? Kill me quick before I go hungry again."

Shirou silently obliged.

"I must thank you, Sir Chulainn. If it wasn't for you, then who knows what could've happened." Spoke the priest, bowing slightly to Shirou. The magus nodded in response, though he kept his eye out on the construction work that was quickly being implemented.

It had been about ten minutes since the villagers cautiously stepped back outside. After only seeing the aftermath of it all, Shirou standing over a decapitated wolf man, word had spread that it had been him who'd stopped the demi-humans.

Shortly after, they were joined by the guards, having finally arrived, questioning him as to what had happened. Curiously, they had nods of understanding, as if the sudden cannibalization was a normal occurrence. The fact that they had arrived this late irked him, but still, with the destruction of everywhere still prevalent, he didn't try to hold it too much against them.

Of course, they left before he could ask his own questions, leaving immediately for the capital, it seemed. Instead, his questions were now directed to the man that started it all, as much as it was tempting to stab him there and then.

"Forgive me if I sound ignorant," Shirou began, "But those demi-humans started eating each other the moment they got freed."

The priest hummed, "You say you're from near Alnus? Yes, that would make sense why you would never have heard of these animals in particular." The man all but spat out, his face contorting into a disgusted glare at the ground.

"Consider yourself lucky you've never had to deal with them until today. They started appearing a few years ago, usually near the north, northeast of the Empire. Stronger than ten men, and with an appetite for meat unlike any other." The priest motioned for them to walk as he continued.

"They eat so much, in fact, that not feeding one for more than three days will usually cause them to starve to death. They make excellent slaves, however, as they are much more capable at physical labor than any other of their demi-humankind."

"That still doesn't explain why they went after each other rather than me. I would have been a common target to them. Instead, they fell upon each other wildly."

"If I recall, they almost always go for the weakest person, regardless of species, so I suppose it may be they realized you were just too strong for them to eat. Or maybe it was because they hadn't been fed today, and that they wouldn't be getting any rations since they're only for us." The priest shrugged, "Frankly speaking, Sir Chulainn, you need not concern yourself with thinking too much on it. Those animals barely think anyway."

Shirou mentally counted to ten as he gripped his fist hard, "...I see. One last question, if you might." The priest nodded with a genial smile, "What exactly are they called?"

"Yaga, my good sir. They're called Yaga."

A/N: If you like what I do and want to support me, check out my P-atreon at P-atreon•com(slash)Almistyor.

And a special thanks to: FireRogueWolf25, brutalcrab and Tassimo.