Muzan got used to his new body in the next few minutes and cleaned up the room, while destroying any traces of blood and dust that might give his presence away.
"It's almost dawn."
While gazing out of the window, Muzan watched the horizon. The sun was starting to rise, and the sky had become colorful.
"I have to hide from the sun until they find Tanjiro's place; what an uncomfortable feeling."
Muzan's eyes twitched. He was a powerful demon lord, yet he needed to hide from the sun like a cowardly bat.
"I guess there's nothing I can do for now. I hope they find Tanjiro soon."
The demon king calmed himself and looked around; he was acting like he was searching for something. After looking around for a while, Muzan walked up to a relatively normal wall.
_Knock_
_Knock_
_Knock_
He knocked on the wall three times, like it was a door instead of a wall. Of course, nothing happened; after all, it was a solid wall.
That is, until Muzan said the secret code.
"Open the door, Nakime."
_Rumble_
As if responding to Muzan's words, the wall shook. And within a few more seconds, a door appeared in its place.
The wooden door automatically opened, and without hesitation, Muzan walked through it. As soon as he went inside, the door behind him disappeared.
He ignored the ghostly phenomena like it was normal. Muzan was now standing in a dimly lit room. At the very center of this room, a female demon was sitting silently.
"I am back at the Infinity Castle; your blood demon art never fails to amaze me, Nakime."
Muzan wholeheartedly complimented the female demon before him. This demon's name was Nakime, and the door was part of her blood demon art, which was called Infinity Castle.
This castle was infinitely large, as the name suggested. On top of that, it was in its own separate dimension.
Infinity Castle was thus impossible to find, and was considered Muzan's base of operations. This castle was how he traveled around the world.
And Nakime, the female demon who owned this blood demon art, was the only demon under him who was considered irreplaceable by him.
"Thank you, Lord Muzan, but I am not worthy of your praise."
Nakime, who was suddenly praised by Muzan, was feeling tense. Her lord had praised her 3 times in her whole life. This sudden praise had caught her off guard.
Seeing her tense expression Muzan was taken aback, why was she so worried? He wasn't trying to kill her just yet, she was still useful to him.
Muzan chuckled and casually walked up to her. Flipping his coat, he sat beside her on the floor then continued speaking.
"You know, I saw the sunrise today, and it felt awful as always."
Muzan said casually; a normal girl would look at you weird if you started a conversation by calling the sun awful, but a demon like Nakime knew this feeling too well.
She subconsciously supported Muzan and complained against that dastardly sun.
"Lord Muzan, you will beat the sun sooner or later. You are the perfect creature."
Nakime held her biwa tightly. Talking to Muzan was always risky, but she felt she needed to show her lord some support.
"Thank you for your support, but I am not perfect just yet. Although soon, I am going to be."
Muzan smiled at her; he was happy and free, as if he was pleased about something. But then, his smile slowly vanished, and he spoke to her seriously.
"The thing I have been searching for all these years, I have found it. I know where the blue wisteria flower is."
"A pair of siblings have eaten the flower, they live on mount Kumotori and their blood contains the flower's extract."
"With their blood, I can finally get rid of my weakness to the sun, and become the perfect being that you speak of."
Muzan suddenly dropped a huge bombshell on her. The news was so Earth shattering that Nakime was stammering to respond.
"Are you serious, Lord Muzan! Congratulations, you will soon achieve your lifelong dream! We must celebrate at once."
She stuttered a congrats while playing a happy melody on her biwa. Muzan nodded and let himself relax, he lay down on her lap while enjoying her biwa music.
The duo stayed like this for two hours, only the melody of a biwa was breaking the silence. After her song finally came to an end Nakime opened her mouth.
"Lord Muzan, will you gain sunlight immunity as long as you drink the Siblings blood, and get the blue spider lily extract?"
Muzan hummed while his eyes remained shut.
"No, just getting the flower in my system isn't enough, I have to expose myself to the sun constantly; only then will I become resistant to it."
Even Nezuko Kamado, who's the only demon to gain sun resistance in the orginal story, had to continously expose herself to the sun and her sun flames, before she unlocked her immunity.
Muzan knew he had to do the same and get used to the buring feeling of sunlight, if he ever hoped to conquer his weakness to the sun.
"Forgive me for my ignorance, but I am confused about something."
Nakime pursed her lips.
"After getting the flower's extract, is it necessary to get exposed to sunlight? Why can't the flower make you immune directly."
A Demon standing under the sun without protection was a life and death risk. Nakime wasn't comfortable with Muzan taking such a risk.
But Muzan knew this was the only way. Eating the flower gets it's genes into the body, and sunlight activates those genes.
"Sorry, I have to do this. Sun exposer and having the flower in my body, are two conditions I must fulfill."
Shrugging to himself, Muzan continued.
"In fact, Doma's men might bring me the Kamado sibling's blood anyday. He will contact me soon."
"In the meantime I should probably get used to the pain caused by the sun. It's daytime currently, maybe I should go out for a bit."
Muzan was thinking to himself. He could regenerate super fast; he had no reason to act too scared of the sun. As long as he wasn't directly under the sun, he would be fine.
"No, Lord Muzan! Going into the sun right away would be too dangerous."
Nakime quickly tried to stop Muzan from doing something stupid; she knew she couldn't actually stop Muzan, if he wanted to walk into the sun. But she had to try!
"No, I have decided. I can't sit around and waste my time. I must prepare myself before getting the blue spider lily."
"Send me to a remote tavern, a place where there are plenty of shadows and a good amount of sunlight."
"I just want to try and see how the sun feels like, shadows are necessary to hide myself if needed."
Muzan got up from Nakime's lap; there was no use waiting anymore. It was dawn right now, and the sunshine outside was pretty weak.
This was the perfect opportunity to do what he wanted. If he trains himself thoroughly, he might develop sunlight immunity sooner.
"Sigh, Okay, Lord Muzan. Then I will send you to a tavern with sunlight and plenty of shadows."
_Rumble_
Nakime helplessly strung her biwa, and a door opened before Muzan. Beyond the door was a dark corner of a tavern.
"Good job."
Muzan praised her again, which made Nakime hesitate for a bit. Did Lord Muzan become nicer because his plan was about to succeed?
Hopefully, she didn't make him upset just now, when she asked him to stay. Just as Nakime was thinking wildly, Muzan noticed her hesitation.
"Nakime; I appreciate your genuine worry for me. You are loyal to me, I am pleased about that."
Muzan gazed at the pale-faced demon woman, who was looking at him with an open mouth. He chuckled and bent down, holding her chin with his hand.
"I have noticed that you cover your face with your hair. Are you perhaps trying to hide your singular eye?"
"You are beautiful as is, but if you want to modify your eyes, let me know when I return, and I will help you."
_Step_
After encouraging his subordinate, Muzan walked out of the Infinity Castle and emerged from the shadows. The door closed behind him and disappeared into the wall.
The tavern wall restored itself; everything was back to normal. Except this time, it had an extra demon as a guest. Meanwhile, on the other side of the door, back at Infinity Castle, there was a flustered demon woman playing biwa music filled with expectations.