Gambit.

That put a bit of a wrench in their plans, since he couldn't just kill Ryuunosuke. He moved to try and take the sword, a tsurugi he noted, from him. That plan was crushed when Ryuunosuke moved abnormally fast and managed to slice his stomach. However Gaius had reacted swiftly and avoided the sword partially, leaving only a shallow cut.

He then tried to restrain Ryuunosuke, tackling him and holding his arms together, as he tried to wrench the tsurugi from him, going all out. But Ryuunosuke’s strength was like that of someone with Touki, and he freed himself and stabbed Gaius through the gut.

“Not expecting this did you? Had you not stood to watch the vision I might not have gotten another living vessel after the last one died.” Ryuunosuke said, in a sneering tone. “I am thankful, honestly. Had you not come when you did I would have languished here, but you did. As thanks I will take your Touki.”

The sword began trembling as Touki flowed into it. However Gaius smiled. He headbutted Ryuunosuke, holding the sword to his body, and punched him in the stomach. Ryuunosuke doubled in pain and tried to take the sword back, however Gaius’ grip on it was strong and he didn't manage it.

“Reiko!” Summoned Gaius his familiar. It appeared in a burst of phantasmagoric blue flame.

“Freeze!”

The familiar understood his master and released its breath upon Ryuunosuke. He was frozen but the ice swiftly began to crack.

“Keep doing it! Don't stop! I have a plan.”

Gaius then did something reckless. He tried to draw the corruption from the sword into him, and his consciousness was absorbed into in.

The inside of the sword was filled with purple fumes. Once Gaius’ thought form appeared in it he quickly tried to find Ryuunosuke.

As he was running in the sword three flaming eyes rose in the mists, and spoke.

“A reckless gambit you did, trapping us here. It is only time before I free my body and kill you out there, and then I'll be free.”

“Ryuunosuke’s body you mean. And that won't happen once I take in all your corruption and destroy you.”

“Ha! I know of your Senjutsu, it's why I didn't take you, too risky. A natural user can't be taken over, that's common sense. And the other man was too weak, without potential, I wouldn't take him. But the kid? Weak and potential, the perfect host. It won't work, I am not haunting this sword, I AM the sword. As long as his bond to it doesn't disappear I too won't. And once you succumb to the corruption I will take it back, and be stronger than ever.”

“We'll see.”

Gaius kept searching until he finally found Ryuunosuke. He was in fetal position, surrounded by a thick fume. His eyelids trembled, he was dreaming. Gaius then saw the sword in his hand and knew the spirit didn't lie. But he would try something else then.

He approached the teenager and grabbed the sword, a representation of the sword’s spirit.

Looking at it closely it was a piece of art. It was abnormally long for a tsurugi, at 120 cm. It had a double edged and straight blade, like all tsurugis. Its handle was 20 cm long and it was a simple wooden one. The blade was unadorned but its craftsmanship could be felt. It was an old blade, and one that hadn't dulled in millennia.

Once he grabbed it Gaius found himself into Ryuunosuke’s dream, one about the forging of the blade.

The blade had its origins in a little farming village in the 10th century Japan. A creature from distant lands had come to the village and had quickly gained its goodwill through the forging of superior tools. For a few years the creature laid low, until it revealed its purpose.

It was a dwarf, one like Fafnir had been. Skilled in forging she had made weapons for the Norse, until one day they tried to kill her. Not unfairly though, the creature had grown fascinated with corruption, and dabbled in dark arts. She kidnapped and killed many, trying to gather enough corruption to build its Magnus Opum. A cursed blade.

However her actions were uncovered, and she had to run from them, until she reached lands previously unknown. It was there that she refined her trade and thought of a great idea, for her at least. She had found a peculiar metal in the bowels of the mountain near which the village rested.

The metal was tougher than any steel she knew of, and with her skills she tried to forge a sword out of it. It was then that she found the metal breaking in her hands. It was aligned with purity and only the pure could handle it.

She thought of a devious plan. She would corrupt the blade, slowly so it wouldn't shatter, and then forge it with the most corruption she could gather. And thus she turned against her hosts. Just that act brought much corruption, something she was delighted with.

She made the children mine the metal, storing it in warehouses so it would soak in the corruption born of the children's pain. But it wasn't enough, and so she made a curse, forbidding the children from speaking under pain of death. After a few died the corruption began to embed into the metal. It also gave birth to wraiths, that brought even more corruption to the dwarfs delight.

The corrupted metal was brittle. She needed to strengthen it, but the metal wouldn't heat. And she came across a way to produce the heat. She used her dark magic to grow trees that fed on the corpses of the adults, creating a coal that could melt the spirit itself. She made the remaining adults harvest it, while making them know of its origin, creating more corruption.

For ten years this state of affairs continued. Until she was ready. She forged the sword and in the verge of its completion she sacrificed a nine year old child, reared in her mines, to bind the corruption she had gathered into it. But she underestimated his hatred, it was so intense it overpowered her magic, and awoke something in the blade.

A Spirit was born. It absorbed the dwarf, the corruption, the wraiths and the curse, gaining the ability to reproduce them, or their skills. And a blade with the dark magic of the dwarf, as well as the ability to produce wraiths and curses was born.

The remaining villagers sealed it away. But one day a man, lusting for power and revenge took it. It consumed it, for it had mind. And from then on it devoured man after man, growing in power, until a monk sealed it away. And for centuries it lay, until the Ablution Society found it. Then it tried to take over one of them, but they paid the ultimate price to confine it within their building.

Gaius wrenched himself free from the illusion. He had been overwhelmed for a moment, for the history of the blade was deep, but his own was greater. He searched and found Ryuunosuke, toiling in the corpse-trees.

He put his hand in his shoulder.

“Time to wake up.”

Ryuunosuke shook awake. He was confused, before he remembered it all.

“How can we escape?”

“We can't. We must destroy the Spirit.”

“How?”

“Fight fire with fire. Spirit with Spirit. I will birth an Evil Spirit from the malevolence I gathered that will devour the current one, and take its place.”

“Won't that just trade my jailer.”

“I can influence what it'll be. I shall guide its hatred towards evil, while making it understand of redemption. That should make it like a child that can be educated. The sword will still be bound to you, but it's spirit should obey and aid you. In other words, you will benefit from this ordeal.”

“What do I do?”

“Relax.”

Gaius reached within, to the corruption he had absorbed. He gathered it and, through knowledge of spirits born from Summoning, made it birth life. However the strain was too much, he couldn't handle the pain of something being born from his spirit.

“Reiko!” He shouted, the familiars spirit contacted him, and understanding the situation shared the burden.

For what seemed like years the newborn spirit greedily sucked corruption in.

In the sword the Evil Spirit began to weaken, and understanding he had lost, surrendered and died.

Akihiko was anxious, now even the bird had fallen. What was going on? He asked himself. At this rate Gaius and Ryuunosuke would die to cold. Thankfully Gaius’ injury didn't bleed anymore, the blood having frozen in the mouth of the stab wound.

It was then that the ice cracked and Gaius and Ryuunosuke fell. Akihiko sighed in relief, the domain was dissolving, it had ended. He called the association for medical attention.

In one of the Waning Moon’s hospitals laid Gaius and Ryuunosuke. It had been three hours and they had fully healed, the medical arts of the Hidden World were advanced and fast.

They were talking when Akihiko entered, followed by the Head.

Akai sighed. “You can't spend a day without doing something crazy can you?”

Gaius looked away, with a sheepish expression in his face.

“Not my fault this time.”

“I know. Alright I know everything that happened so I just want to know what the damn sword does now.”

Gaius signaled Ryuunosuke, but he had something to ask.

“Actually I don't know what happened.”

Akai accepted those words and explained.

“You know about the spirit, right?” Ryuunosuke nodded. “Well then, the rest is easy. Due to it being part of the sword the spirit needed a host to wield it. It would, however, take over them. When the Ablution Society discovered the sword in a ruin they took it, intending to destroy it. It didn't work.

The spirit was sealed by them before they died so it could only form a domain. Once you entered it tried to take over you, and you know the rest.”

“That's what I don't get. What is a domain.”

Aka I raised an eyebrow. “You didn't tell him Akihiko?”

“Didn't come up yet.”

“Sigh. Well a domain is an pocket dimension. This pocket dimension resides within normal space, but it doesn't obey normal laws. It follows them, but they are altered a bit in order to benefit the domain master. Any being with sufficient spiritual weight, so to speak, can form one. It's complex magic, but easily made once you know how. The domain tends to reflect the masters nature. It's because of this that this domain produced and gathered corruption. It also makes them the most comfortable place for the domain master to reside in.

Think of it as a place in which the creator has home field advantage, and can use supernatural powers more easily. 

I can, with enough time, form a domain, and so can Gaius. But if you leave it it dissipates, so it's not very useful for us.”

“I see." Ryuunosuke nodded, before explaining the swords capabilities. "The sword can make ice and fire, it's intensity depending on the Touki I put in.”

“That comes from Reiko.” Commented Gaius.

“It also slowly nurtures my spirit and body until I get Touki, but after that the effect stops. It can hasten with training.”

“Me.”

“It grows sharper and tougher with ki or Touki, and takes part of the burden of casting magic. Making me a better mage. An all around boost.”

“The original spirit. Without the evil parts.”

“I'm impressed Gaius, you made a great spirit.” Complimented Akai.

“I know." He smiled smugly. "Though it wasn't intentional, I was stumbling in the dark there. It was a gamble, to be honest.

Also as Ryuunosuke grows so will the spirit and sword. It will never be useless.”

"Then we are done with this interrogation. Ryuunosuke I will get you sword and ki training, once you gain Touki you will join Gaius' class." His voice made it clear there was nothing to discuss.

"Yes, Master Head."

"Gaius, how do you feel? Are you healed enough to go to class?"

"Fine and yes. It hurts me that your first concern is class and not my health."

"Spare me the melodrama. You know as much as I do that magical healing is incredible. Your health was never into question."

"It's the thought that counts."

They kept making small talk for a few minutes. Akai was about to leave when Ryuunosuke shouted.

“What?!”

“What's wrong?” Asked Akihiko.

“Two voices spoke in my head!”

“Two. Uhngh.” Groaned Gaius. “I wasn't ready to have twins.”