A Hashira's Demon

Master of the Mansion

As I regain conscious from the pain, I looked around as I noticed the location was a bit different than before. What I expected to be sunshine and gravel ground instead was a soft bed with tatami mats. While pondering the reason for the sudden change, I started to smell something interesting near my presence. As I turned, it was a small bowl of udon filled with fried potatoes. Unsure if this was a trap, I slowly crawled towards it and reached towards one of the potatoes.

"So, you're finally awake." a voice interrupted.

I looked to the side, only to see a strange man looking outside. Even though I was unsure if he would strike me or not, I sat back down and bowed lightly. His voice was more similar to my brother Muzan, but nothing like this: calm and gentle like rain and breeze.

"No need for formalities, we've met before, you know."

I looked up lightly, to see if his face was recognizable. Only to see what appears to be poison coursing through his veins. I wanted to reach towards his face to cure this disease, but it seems impossible for me to determine its origin right there and then.

"I know that your eyes are seeing my wounds, my child." he replied, "but this disease is not one which can be healed by any demon, I'm afraid."
"But why?" I asked, sitting down respectfully. "Why can't any demon heal this wound?"
"Because this wound is genetic. It has been passed down from my family for generations and it shall continue this way until I die."
"But if I were to heal you, then maybe-"
"I would have no other purpose if this wound would be healed right away."

I was surprised by his response.
He wants to suffer with this disease?
But why?
He mentioned it would defeat the purpose if healed.
What did he mean by that?

"What I mean is:" he explained, as if he had read my mind. "if my disease would be healed immediately, then my hatred for your brother would all be in vain."
"My... brother gave this to you, my lord?"
"Yes."
"Then I can reverse it! Please just let me-"
"I appreciate your offer, but I must humbly decline. Your heart is pure whilst other see simply the eyes of a demon. Isn't that right, Moon Demon?"

Wait. He knew?
But how?
Did Rengoku told him?
And if so, did he tell him what my true intentions were??

"No need to panic, my child." he cooed softly, "I have no intention of harming you, despite how my slayers treated you before. They only fear what they don't understand, but that's no excuse on how they handled it properly. I sincerely apologize for that."

He placed his hands towards his lap, giving me permission to come close to his location. I slowly crawled towards him and sat next to him, afraid to have my body touch his own. With one reach, he brushed my white hair as he calmed me down.

"If you ever need a place to stay, you are more than welcome to stay here. Our doors are always open for you."

This was one of the calmest people I've ever interacted before.
Not even my brother can calm his underlings like this.
As I slept calmly from his touch, I felt a strange presence echoing in my mind:

'Did you really expect you to betray me like this?!'

I backed away from the Master as fast as I could as I shook in fear.
He was looking. My brother. Through my eyes.
I started to cover my body in fear, crying lightly.
The Master was surprised by my response and smiled lightly.

"I understand." he replied. "Kibutsuji has spoken to you about your demise."

I nodded lightly.

"Then you must leave for the time being. You didn't come here to harm one of my Hashiras, are you?"

I froze.
Does this being know all, similar to my brother?

"Do not fear, my friend," he reassured, "Rengoku will understand your departure by my words. Now go. My crow will escort you to safety."

He was willing to let me go.
Even though I'm a demon and he a master for the demon slayer corps.
This Master has a kind heart, especially towards a monster like me.
I kneeled again and bowed in respect.

"I thank you, young Master."
"No need."

As I got up to leave, I turned to the side for a moment.

"Young master, if I do return, may I bring a friend of mine who could help you learn about this disease? She would be very interested about this very much so since she's actually a doctor herself."

His expression was in complete and utter shock.
A demon made a request to return... towards the master of the mansion.
Despite all the warnings he has given me to this day.
With a slight nod from him, I walked out the door.
Just as I was about to leave, Rengoku stopped me midway.

"My love! You have come back! How are your injuries? Did Sanemi hurt you as much? I swear to the heavens I will hurt him just as he harmed you!"

As he continued to ramble on and on, I started to feel a bit uneasy for a moment.
On one hand, I want to stay and protect Rengoku with the remainder of my demon life.
On the other, my brother may intend on sending more people to kill him.
I couldn't do that for him.
I had to protect him.

"Rengoku-"
"Not to worry about that, my love!" he continued. "We shall see to it that you shall be trained to be a better fighter, in order to keep you safe from other slayers, and-"
"RENGOKU!!" I yelled.

He stopped talking and looked right at me.
I sighed since I knew this would be the hardest thing I've ever done in my life.

"Your master has sanctioned me to fight demons." I lied, "So I need to go to a mission distance beyond this location."
"Really? Your very first mission? That's great news! Then you must hurry! Those demons aren't going to wait themselves! Take care now, my love! I hope Senjuro and my father can get to see you again when you return."

I nodded and turned to leave. My undead heart started to break as I knew the Master would tell him the truth about why I left. However, this has to be done. One way or another.