Title: No Going Back
Author: raikune
Rating: T for angst
Summary: Kakashi makes a choice - he will awaken and use the deadly Sharingan Mangekyou. But path to obtaining it is a monstrous one, is he prepared to make the necessary sacrifices?
Warnings: Spoilers for chapters 385 concerning the Mangekyou/Uchiha history. I do NOT know how Kakashi actually got his Mangekyou, this is a suspenseful pre-Mangekyou fic (does that even makes sense? Gah).
Notes: Originally written for the 31days LJ community under the title 'The Ultimate Weapon.' The theme was "Hell hath no limits."

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In a way, Kakashi blames himself for Sasuke's betrayal.

He feels if he'd just talked to the boy a little more, made more of an effort to understand him, maybe things could have turned out differently. Maybe Naruto – only twelve, already scarred, heartbroken – wouldn't have spent the night sobbing into his shoulder. Maybe Sakura wouldn't have looked at him with dull, shattered eyes: and in them, a glinting hint of blame.

Kakashi knows he's failed as a teacher and a Jounin. And, perhaps, as a father.

It's odd to think of himself that way, but it's true.

Naruto is already half a son to him: he's known the kid ever since he was born, helped him take his toddling first steps. There's a picture in his wallet of Naruto on his shoulders, with his father the Yondaime standing behind them, a proud hand on both their heads. Looking at it breaks his heart.

Sasuke was his own the first instant they'd talked together. Sasuke was what he had once been, long ago, before Obito had pulled his head out of his ass. Kakashi smiles grimly: him and Obito, Sasuke and Naruto…history had a way of repeating itself. He hopes for their sakes that Naruto can rescue the Uchiha in time.

It should be him running after Sasuke, he knows. If it had been him, his sensei would've dragged him back by his hair and probably tied him to his bed. Kakashi groans: he can picture this all too well.

However, Namikaze Minato had been a stronger man then him. A better man.

Well, he would have to get stronger too. He wishes he could find Itachi and beat the shit out of him for ruining Sasuke's life. For destroying what little family he'd found.

Kakashi sighs.

If he's going to fight Uchihas, he'll have to take his Sharingan up to the next level. Hethinks that maybe he's figured out a way to do it. Thanks to Tsunade's help and some rifling through the archives, he's found what he wanted: old tablets. Old, chipped, burnt tablets. Uchiha relics, chronicling the fascinating history and secrets of the Mangekyou Sharingan.

He's pored over them for hours, almost every day, trying to understand. The words chill him: the Mangekyou is an evil technique. To achieve it is to damn yourself and wash your soul in a sea of blood. The process requires more emotional pain then he's prepared to go through. And, of course, there's the darkness…the price you pay…

But such power. The Jounin is stunned. To be able to control the Demon Fox! To say nothing of the jutsu techniques that accompany the Mangekyou, unique to each Sharingan user. Kakashi can personally contest to this, he's been killed over and over again by Itachi's deadly genjutsu. He wonders what sort of powers his own eye has, locked behind its iris.

Thinking about it makes him nauseous and exhilarated.

He remembers the conversation he had with Tsunade in her office, on whether or not he should try for the Mangekyou. It had only been a week ago…

---

"What you're doing is dangerous," she said. "You don't even know if you have the ability to tap it. It might only be accessible to those of Uchiha blood."

"My regular Sharingan works fine without that blood."

"That's different," she snapped. "This is completely different eye technique."

"It looks like to me all you need to awaken the Mangekyou is a lot of willpower and ruthlessness," he responded lightly, glossing over the bloodier details. The Fifth isn't fooled. She stares at him solemnly, a little sadly.

"No one's asking you to go through this, Kakashi-kun."

His heart pangs. How long had it been since she called him that?

"I know. But look at what we're facing. I want to get stronger, Tsunade-sama. And you know what it would mean for Konoha…to have a Mangekyou user in the Hidden Leaf…you know the kind of power it has…"

"What's the price for all that power, Kakashi? You would end up like Itachi? Or Madara?"

The copy nin said nothing.

"I've read the tablets." The Godaime sipped at her green tea. "Brother killing brother, friend killing friend…how would you even achieve this?"

"It doesn't need to be a brother or a friend," he said haltingly. "It just needs to be…someone or something you love. Something important."

"I can't believe you just said that."

"There is no other way." His voice is quiet. "Don't you think if there was another way I would try that instead?"

"Who are you planning to kill, Kakashi?" Her grey eyes ran over him. "Who are you willing to sacrifice?"

"No one. Yet." He slumped in his seat. Very quietly: "I don't want to kill anyone."

He thinks: I don't want to do this. I need to do this.

I don't want to kill anyone.

She takes his head in both her hands, brings it forward and kisses it.

"Until you find the answer to that, Kakashi-kun, you can't go through with it."

"I'm going to hell, aren't I," he muttered.

"So don't do it."

"Goodbye, Hokage-sama." He pulls away from her and leaves, not looking back.

Kakashi rubs his face, bringing himself back to the present. Back to his predicament: who or what was he willing to sacrifice?

The Jounin stares out his window for a long, long time.

Most of his precious people are dead. Those who becoming precious to him now – Naruto, Sakura…he wouldn't touch them, even if meant awakening the strongest Mangekyou in the world. No. It had to be something else.

His Sharingan eye begins to tingle. It's been doing that a lot lately.

In his mind the death of Obito begins to replay, again and again, on an endless loop. Obito would not stand for Kakashi thinking such thoughts. Obito would never try and awaken the Mangekyou, because to do so was too monstrous and he was too kind. If Obito knew Kakashi was trying to achieve the unthinkable with his Sharingan eye, he would've screamed.

His borrowed eye burns. Kakashi rubs at it, sweating and grinding his teeth.

Forgive me, Obito. This is something I have to do.

---

In the meantime, while he ponders the horrendous, he'll continue to reach toward it. He practices uses the Sharingan every day, pushing it and himself to its limits. Experimenting. Stretching. Changing. Manipulating. It makes his head hurt and exhausts his chakra, but at the end of each session when he's bent over and panting, he feels a little stronger.

He feels a little closer…to what, he's afraid to say. Something is unfurling in his mind, behind his eye. Something he can almost grasp. Something that can almost grasp him…but not yet. Not, perhaps, until he's made a sacrifice.

Kakashi can feel it, that alien something, humming behind his eye. He thinks sometimes others can feel it too, see it. Gai has been giving him odd looks lately. So has Tsunade, scrutinising him with a tight expression on her face. He gives little reports of how he's progressing every other day or so, telling her how he's almost reached a certain state: one in which he will be able to awaken the Mangekyou. It makes Kakashi dizzy, frightened, exhausted. He has headaches that linger now, but that's nothing compared to that hot, coiled, delicious feeling in his left eye.

He is still lacking: what the Mangekyou requires is blood.

Soon, though. Soon.

The power of Uchiha Madara is almost in his grip.

-end

A/N: Reviews are welcome. :) And no, you aren't as awesome as Kakashi :D But you can write about him!