Ai sat on the porch of Demon Slayer Corp's Meeting Spot with a flushed face. She was twitching from all the praise she was getting from the Master of Demon Slayer Corps and the other Hashira.

After being healed and resting for a day or two, they returned, and this time, they brought good news. Since she couldn't say that the System calculated it, she had to say that the moment she was near her death, she had the enlightenment, and she saw the trust for Grand Fire Breathing Techniques.

The reason why everyone was praising her was that the process was simple and complex at the same time.

The simple part was that it needed a perfect flow, from the First Form Flow to the Alternative Form and back to another Form with another Flow.

The Question was that they had to keep the Flow, which meant needing the Perfect Technique, the puzzle piece that kept it going.

When they were overlapped forcefully, the damage was too much. It massively drained the stamina and did cause some damage to the body, but it was now viable.

That was what System had figured out, making her smile, 'Hinokami Kagura, the Dance. The Sun Breathing. It all makes sense now.'

Since Grand Fire Breathing was closest to Sun Breathing, they too had a similar structure.

This was why something rare was happening, with almost all Hashira here, training to figure out their path to Grand Breathing Technique.

This all seemed like great news, but the truth was, every time they made progress, they were overjoyed, and so every time they saw her.

"Great job, Ai Senju! You are the savior of humanity!"

"Brilliant!"

"As expected of Miss Ai!"

'Yes,' Ai sighed, hearing praises from everyone praising her, putting her on the pedestal.

After all, they would grow much more powerful with Grand Breathing Techniques. Enough that they were confident enough to fight against the Demon that defeated Rengoku and not die. At the same time, about three of them were confident about killing it.

This training was to go on for months, and she planned to do it too; after all, she couldn't use the Grand Breathing Techniques to fight.

The only reason she could even fight the Twelve Kizuki was because of the strength that Wood Breathing Technique granted her. Without that, there was no way she could ever hope to survive in front of the Upper Level.

So she started training too. If she could master Grand Breathing Techniques, she could keep her regeneration and fight against Twelve Kizuki.

Although, before she could start training, there was one single problem.

"Konoe, I am so sorry!! Please don't be mad at me!"

Konoe stepped closer to her without showing a single expression on her face.

Ai squeezed her eyes shut, only to feel Konoe's arms around her neck, hugging her, "Next time…I am coming with you."

Ai gently opened her eyes, smiling, hugging her, "Ah, I can't reject that. Please, protect me next time."

"Mm," Konoe stepped back, taking her sword before leaving to practice.

"That girl, she had been practicing non-stop," Shinobu smiled, "Since your Grand Techniques only help the basic five elements, we have a much bigger hurdle if we want to figure it out."

"Right," Since she had only made Reverse Technique for Five Elements, there was a much bigger hurdle for others. And even if she used the other ninja techniques, like the one for Sound, Sand, Metal. It wouldn't matter if there were no one here to use them.

It might be enough to leave behind more techniques for the future generation to master, "Hehe…."

She didn't plan to leave anything for the future generation; she wanted to end this in the now, in this generation, and hopefully in the next few years.

That was all in the future; now, all she wanted was to sleep for a week or two.

Ai entered her room, dropping onto her bed, but a good night's sleep wasn't what she got. When she entered the world of dreams, dreams weren't what awaited her but memories.

She stood in a place where numerous insides of a Japanese-style house was stacked, in different direction, formation, forming a maze of a kind.

But rather than the fantastic place where she was, her eyes were on a Demon and the girl whose arm had turned into something monstrous as she held the Demon in the sky.

"Forgive me!!!!!!!!! Lord Kibutsuji!!!"

"That's Muzan…Kibutsuji?" Ai turned her head to the girl or the guy dressed as the girl between five Demons, with one of them dead; there were only four left.

He killed the first one, moving his eyes towards the other, asking, "Do the Demon Slayers scare you more than me?"

"NO!" The Demon hastily refused.

"Every time you encounter a Hashira, you flee."

"No! Lord! I risk my life for you!"

"Are you contradicting what I say?" Kibutsuji slammed his ugly, overgrown hand down, killing the Demon.

One of the three Demons left decided to run, but none of the others reacted.

Kibutsuji moved at a speed that the Demon, whose memory it was, couldn't see and brought back the head of the Demon that ran before anyone could blink, "I think that the Upper Ranks are all I need. I need to dismantle the Lower Ranks."

And the next one tried to explain but ended up dead too. The only one that survived was Enmu because of his sadist nature.

But what brought her attention was the following words that left Muzan's lips, "If you also kill the slayer with earrings that looks like Hanafuda Cards, I will give you more blood."

Ai sat up in shock, gasping for breath, wiping the sweat off her face. She slowly sat up, walking out of the room. On the way, she found Tenjiro, Zenitsu, and Inosuke training, and so she called them while telling Aoi to call for other Hashira, tell them she had a dream.

It took a while before everyone gathered in place, and it took a bit longer before Master was there, but when they were, she repeated the contents of the dream to them.

"Does that mean that all the Lower Kizuki are dead? That's flashy," Tengen Uzui raised his head, narrowing his eyes.

"But it's more important for us to figure out why Muzan is after Kamado. Because he saw him? Or is it something else?" Rengoku shot a look towards Tanjiro, who scratched his cheek, while Zenitsu was hiding behind him, trembling as if Muzan was after his life, not Kamado.

"About that, I have an idea that one person might know the reasons behind it," Master Kagaya spoke up, bringing everyone's attention towards her, "But I'd request that you not raise your weapons at her."

'Not raise your weapons?' Ai widened her eyes in wonder, coming to an answer when she came into their view, "Tamayo!!"

She didn't have time to think, she sucked in a cold breath, activating Wood Breathing Technique, and she appeared in front of her, blocking the attack from Sanemi while Rengoku blocked Obanai Serpent Hashira's attack.

"Stand down, I am the one that asked her to come, and I gave my word that I will lay my life to make sure she leaves here alive!" Rengoku loudly declared, making both the Hashira look at him as if he were crazy.

"Rengoku!"

"I said!! Stand down, didn't you hear what master implored!!"

Sanemi and Obanai grunted, backing away from Sanemi, pointing his sword at Rengoku, "What is the meaning of this! Rengoku!!!"

"Hear her out," Rengoku narrowed his eyes, "If you still think she is untrustworthy, you can kill her and me. I will not resist."

Yushiro clicked his tongue in annoyance, looking away when Tamayo smiled, "Did you know that all Demons are cursed, and they cannot reveal anything about Muzan Kibutsuji or even take their name?"

"Didn't you just take his name?" Shinobu narrowed her eyes.

"Right, because I was freed of the Curse, hundreds of years ago, when Demon Slaying Corps started gaining power when Breathing Techniques came to be, and when a Demon Slayer cut Muzan Kibutsuji's neck."

"Absurd! Every Demon dies when their neck is cut!" Sanemi raised his sword at her, pointing towards her, "Do you think you can fool us?"

"Yes, that was when Muzan was closest to death…only, he evolved at the last moment, and that weakness…it was no more. The one who cut his neck was the First Demon Slayer, the wielder of Sun Breathing Yoriichi Tsugikuni, and I was there at that time. I broke free of the curse when Muzan was at his weakest and since that age. I have been trying to find ways to kill Muzan Kibutsuji."

Mist Hashira Muichiro broke out of his daze a little, repeating the name, "Yoriichi Tsugikuni."

"Yoriichi was a prodigy from the day he was born. He is the creator of Breathing Styles and created the First Style, Sun Breathing," Tamayo glanced towards Tanjiro, smiling, "Also, he sported hanafuda earrings."

"Wait…hanafuda earrings and Sun Breathing? Huh, huh, huh!!!!!!" Zenitsu backed away from Tanjiro, pointing at him with a shaking hand, "Is It possible!! Tanjiro! Are you a descendant of that person!?"

"I…?" Tanjiro widened his eyes in disbelief, looking at Tamayo, who shook her head.

"I can't be sure. I can be sure that you have a Fate with Yoriichi, and I am not the only one that feels that way. Maybe Muzan felt it too when he saw you, and so…."

"So he is trying to kill Kamado," Shinobu said, "That does clear things up, but that is not why we trust you."

"About that," Tamayo sat down, "I have been researching ways to kill Muzan; with Grand Breathing Techniques, the hope has drastically increased. Well, about time since I found a way to turn Muzan back into a human."

"Muzan…back into human?!" Shinobu and almost every Hashira focused on her.

"Absurd! Now you are spinning fairy tales!"

"Nezuko…she doesn't need to feed, sleep. With her blood, and the blood of many Kizuki," Tamayo didn't tell about Ai's blood, that was overbearing, enough to kill Muzan from inside out, "I have been able to come up with an antidote. If Muzan is fed this, he will turn human in a few hours, the end of Demons."

"Although, he'll lash around, which would be a disaster. Which is why I am here."

"How can we even believe that you created something like that? It might be a trick you are using to expose us to the Demon?"

Kagaya smiled, "I can vouch for her. She wants Kibutsuji dead as much as any of us would."

"Even if you say that, how can we even reach Muzan? We don't even know where he is. How can you help with that?" Shinobu asked.

"We'll draw them out," Kagaya glanced towards Tanjiro, "Now that Tanjiro has been able to perform Sun Breathing, knowing about the flow, it's safe to assume he can take on one of the Upper Kizuki, right?"

Rengoku nodded, "Right, maybe Upper 5 or Upper Six, too, with some help."

Tanjiro was relatively calm, even though his heart was blazing. He got the message before others, telling him that Nezoku could be turned back into a human, and he had already fed her the pill. Now, she was resting, and Tamayo would stay and observe the process.

He scratched his head, "I can only perform a few forms…sadly…my body can't handle performing the full dance."

He let down his hand, breathing in, "But I am sure that I can easily defeat the Lower Kizuki 1 and even fight against an Upper Kizuki."

Tamayo smiled, narrowing her eyes, "Muzan, he's so scared of Yuriichi's Memory. Wonder what would happen if one of his men is killed by the same Sun Breathing, it would drive him crazy with fear, and he'd send more, and the more you kill, the closer you'd get to Muzan."

"You say that, but where do you plan to find one? An Upper Kizuki?"

"Hm, there is one in Entertainment District; she has been there for nearly a hundred years, if not more."

"What? Did you say Entertainment District?!" Tengen Uzui took a step forward, growling.

"Right," Tamayo gently nodded, and Uzui's whole demeanor changed. He pointed at Tanjiro, Zenitsu, and Inosuke, "You three! You are coming with me!"

"No, wait," he looked towards her eyes, seeing her beautiful visage, "Right, you are coming with me as well! We are going to kill this Upper-Rank Demon!"

"Wait, should more of us go? In case it's of a much higher rank?"

"No, we can be in nearby cities as backup," Rengoku said, "If it's Upper Rank 1 or 2."

"Then I am going," Shinobu took a step forward, "And I will take Konoe with me."

"You," Tamayo appeared in front of her, whispering something in her ear, and Shinobu hesitated.

She sighed, "Fine; someone else takes my place this time. I'll be right behind you guys."

"Then, I will go," Sanemi raised his hand, but Kagaya shook his head, "Giyu, you and Mitsuri go, be near the towns or village near Entertainment District and wait. Ok?"

"Wait, Master!"

"Sanemi," Gyomei spoke up, "Master has Master's plan."

"Fine!"

"Right, since that is done with, Four of you, come with me!"

"Huh? Wait, wait, I have to take my things!" Ai didn't even get a say in it when Uzui held the three boys in one arm and raised her over his shoulder with another.

"My weapons!"

"We'll stop on the way!"

Tamayo watched them leave, chuckling to herself, "It seems that girl is getting along with everyone."

"Ai…? Yes," Kagaya smiled, "Then, we should start preparing for it."

"Right."