Yakumo looked at the training grounds of team 8 in horror. No! Why did she choose this place! It was like a persistent thought she couldn't get rid of.

He survived me here due to luck. Now, we remind him not to mess with us.

WHO was thinking that!?

It was me.

Just then, Saul put his hand on her shoulder. "Are you ok, Yakumo? I know you must be feeling really guilty to have thought of this place."

She was not ok. She needed to go back to the real world and find her Kunai.

Why? He could clearly make you feel better.

SHUT UP!

"Saul..." She tried so hard to force a smile it looked as if she was about to cry. "I need to go back to my room."

"The issue though, is in here isn't it? Yakumo, it won't do any of us any good if you keep running away. You need to face this directly."

"But how Saul! How? Whatever it is, it's in my head! Talking to me, doing horrible things. No, it's me. I'm the evil one. I'm not running away!" It was just as her mother always said. You're a demon.

"Have you tried manifesting it? This is Genjutsu. A world where your will becomes reality. If you believe me, you shall see it for yourself. Bring it out!"

If Saul was Yakumo at this moment, he would've felt like what he was being told was complete and utter bullshit. However, what in the hell else was he supposed to do? He wouldn't be speaking like this if he didn't know what happened in Canon! There really was a demon!

Yakumo closed her eyes. The entire world went dark for a moment. When she opened them again, there it was. What in the... Wait. Her thoughts. It was just her now!

A disordinate voice, Yakumo's soft, feminine voice, but mixed with a deep rumbling baritone, spoke. 

"Hello Yakumo. I am... Id."

A figure, made in what seemed to be a mockery of her likeness, stood before her. Although dressed in her normal pink yukata, everything else was... Wrong. Its arms hung all the way down to its knees. Its skin was an ash grey. It had terribly long nails, like the talons of an Eagle. Its hands were partially made of bone.

And its head. Its face. Oh, it was horrible! Where her ears should be were long, elongated horns that pierced outward like two lances of steel. Its face lacked any sort of lips; its teeth were barred and had fangs extending past its chin like a saber tooth tiger. Its eyes were completely black! Yet, it was still adorned with her beloved hair bobbles. Was it trying to look cute!?

"Eh he hehehe~!"

It blushed! Yakumo was positively horrified. 

Saul put his hand on her shoulder, not really entirely sure what to do. He was kind of winging it at this point to be honest. After Yakumo's complete crash out when it killed her parents, Id stopped acting out in the original series.

Even when Naruto, Kurenai, and the others came to try and kill it, the being only intervened once Yakumo tried to end her own life. Even when it fought Naruto, it was merely playing around, constantly holding back. Otherwise the crystallization of Yakumo's power, the being with the power to put all of Konoha into Genjutsu at once, would not draw against a kid wielding merely a single kunai. Especially within its own Genjutsu world!

From these two points alone, one could reasonably deduce that Id was really not as evil as the series painted the being to be. Rather it was most likely an immature entity of incredible power merely doing its best to protect Yakumo's well being in its own, naively simple way. It had likely learned from Yakumo's feelings and reaction to her parent's death that killing anyone she cared about would only make things worse.

Or maybe it really was just a stupid, evil demon that just did whatever it wanted - and those events just happened to all coincide. Saul wasn't sure.

"Yakumo... Try talking to it?"

She whipped around to face him with shock. "What!?"

"Well, I mean, it's just standing there. Might as well, right?"

Yakumo took a deep breath, trying to settle her rapidly beating heart. "Who... No, what... Are you?"

"I am what I am. My name is Id."

"Why! Why are you here? Inside me!?"

It tilted its head curiously.

"You birthed me, shaped me. I was nurtured by your mind."

"What? No, that's not important right now. Why did you try to kill Saul? Do you realize what you've done to me!? My dreams of being a shinobi to make my father proud, my chance to finally prove my mother wrong, everything I've worked for my entire life! All of it is in jeopardy because of you!"

Id shrank.

Saul was starting to understand. Chakra, it carried will and memory. Saul knew this already from the many examples, whether it be Kushina and Minato's last farewell, Asura and Indra's reincarnations, Orochimaru's curse mark, even the very existence of Genjutsu itself. But now her conversation with Id started to paint a picture.

Her consciousness was so strong, even its subconscious could manifest itself as a separate entity. Yet as Genjutsu is guided by belief, intent, so too was Id shaped by her perceptions of her Kekkai Genkai. She had always been told that a demon lived inside her. Once she believed it, it was created: her demon.

It called itself id as an indication of this. In psychology, Id represents one's base instincts and desires. The demon's origin was never fully explained in canon, yet its true identity was hidden in plain sight.

Rather than trying to explain all this, Saul took a simpler approach. "Yakumo... This thing. It has only acted in your defense right? Even if it did try to go overboard, nothing bad actually happened. Look at it now! It's not attacking."

Yakumo looked up at it fearfully. It really wasn't... doing anything? "Why did it try to hurt you? I didn't want that!"

Saul deadpanned. "Why are you asking me? Talk to it! You're the one in control here - it's your kekkai genkai!"

"It's freaky! I don't want to! Tell me!"

Yakumo! How are you so useless! Saul thought for a moment. "Let me take control of your Genjutsu world. See if I can control it."

Id hissed, "Don't do that. His heart is filled with greed, desire. We can feel it."

Yakumo frowned at it, then looked over at Saul pleadingly, "I don't care. I want this... this thing dealt with! How do I give you control?"

"Just say it. With your spoken permission I'll be able to."

What was in a Genjutsu was defined by intent, belief. It's an odd way the mind works - documented by the placebo effect. Just by believing you were taking beneficial medication for an illness or injury, your body would recover from it faster, regardless of what was actually in the pill or medication. In the realm of pure consciousness, within the body, its effect was paramount.

"Ok! You can take control of the world! It's yours, Saul!"

The Genjutsu world immediately went back to a mimicry of Yakumo's room, although quite a few details were off this time around. Saul constructed a giant cage around Id, to Yakumo's visible delight.

Saul was brainstorming ways to seal Id within him. The power gain would be immense, and if he could control it the same way he could now with Yakumo's assistance... Well, he had no clue about how to seal things anyway. The only Ninja he knew had any Fuinjutsu ability from Konoha were Danzo, Hiruzen, Jiraiya, and Kurenai. None would help him with stealing her power, nor buy the excuse of him 'helping' her by doing so. He would have to find another way.

"Yakumo. This cage I've created is with your power. Without your desire to open it, Id can never get out. So don't ever let it out, if you don't want to, ok? I'll meet you occasionally to check up on the cage, so no need to worry."

"Yes!"

Author's Note: Alright I've written this ch in a hurry since I'll be busy today, hopefully everything is good. Ill be back w/ another ch later today