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Playing with Fire

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Muzan may not be a God (yet), but he certainly has the patience of one. After all, it must mean something if he’s gone through almost a thousand years without his plans successfully coming to fruition. Nearly a thousand years of dealing with incompetence and irritating pests.

His commands are not difficult are they?

One: Locate the blue spider-lily.

Two: Destroy those weak human demon slayers.

Three: Serve him with undying devotion.

He only has three simple tasks and in exchange he gives them power, immortality, and knowledge.

Instead, he’s met with frustration and disappointment. Rather than having powerful and competent demons at his disposal, he has children and disobedient ones. Children are useless fools aren’t they? They are unable to comprehend and complete the simplest of things.

He may be the creator of them, but he has no intention of raising them or acting as their parental figure.

This includes the Upper and Lower Moons. Perhaps, he has been too lenient on them just because they are the Twelve Demon Moons. They squander his gifts away and are easily pleased by only accomplishing a fraction of their job.

Eating humans? That is nothing special. It’s what he expects them to do.

Growing stronger? That’s their purpose. To grow and evolve in order to be valuable to him.

Killing one Pillar? How utterly meaningless. What about the rest of those so-called hunters and especially the Ubuyashiki family. They are and have been a nuisance for as long as he can remember. 

In order to stop an infestation, one must find the source and purge them all.

He needs to discipline them more and remind them why they exist in the first place. Without him there would be no demon; each and every one of them would have died long ago as a powerless and pathetic human. They should be grateful.

Of course with enough discipline, children learn and his demons will learn. They all learn to realize how insignificant they are before him.

Unfortunately, many of the demons all enjoy testing his patience and before he knows it, their heads are gone. And well, it’s justifiable, they don’t need their head in the first place if they can’t even use it to understand the simplest of things.

Just who do they think they are?

In the end, there is no room for insubordination or weaklings. They are all easily replaceable.

And yet, here lies a child who dares to challenge him.

Those dark red eyes are always ablaze, stubborn, and headstrong. No matter how much he pushes, the child faces him back defiantly and pushes back. No matter how futile the resistance is.

If it was any other demon, he would have killed them without any hesitation. So he wonders why he allows him so many liberties?

There’s more reason to keeping him than just for entertainment and revenge.

In the midst of the chaos and screams, only one of them made an impression on him. He is certain if that boy was given a chance to hold a sword, it would come to haunt him. Only that child’s eyes burned so dangerously to resemble that man.

Speak not of his name for that may invoke something.

Though, why would he need to remember something so trivial? That human is beneath him and dead.


Still... the ache, the reminder, the memory, the humiliation remains seared into his existence. He was nearly killed by some human.

Those hanafuda earrings.

Muzan suppresses a shudder and curls his fingers into the palm of his hand tight enough for his nails to pierce his skin.

He absolutely loathes this sensation. How his body continues to remember.

“Why do you continue to fight me?” Muzan mumbles to himself as he gazes at Tanjiro’s sleeping form on the bed at one of his hideouts.

The boy is probably the worst demon he’s ever created and by no means does he mean that Tanjiro isn't strong. Tanjiro is far from that, he has the potential to be shaped into a great weapon.

Rather… Tanjiro doesn’t behave like all the other demons that have been created by him and the other Upper Moons.

Now he doesn’t usually care how many demons he’s created and executed as long as they serve him. However, this is the first time he’s created a demon who reeks of empathy. A demon who still clings onto pointless morals, refusing to mercilessly murder and devour.

How utterly annoying and disgusting.

And yet, why… why does he permit such a thing to remain by his side?

What is special about this child besides his heritage or connection to that sun-breather?

There is a warmth that the demon boy emits that all his other demon do not. A feeling that he has not felt in a long time—


He refuses to admit or even think that he could miss the warmth or the rays of light. Rather… the mention of the sun causes his blood to boil in rage. He, Muzan fears nothing because there is no demon nor human who could stand against him. The sun is the only thing that stands in his way of perfection and forces him to cower away to the dark corners of the world.

Tanjiro reminds him of his own weakness and at the same time what he yearns for.

Tanjiro resembles the sun.

In an instant he could kill him from the inside out, the blood that flows through that child’s vein is his blood. Even without doing anything special, he could bring one hand towards that small throat and...

“There is no escape from me, Tanjiro.” Muzan Kibutsuji curses as he rests his hand along the boy’s thin neck.

The child’s sleeping face scrunches unpleasantly as if suffering from a nightmare and incoherent words spill from his lips. However, a pale finger gently traces the boy’s face from his scar on the side of his forehead and moves down to caress his cheeks. The discomfort instantly dissipates from that single motion and a relieved sigh escapes from the child.

A repetitive movement he’s done consistently to the boy, reinforcing that he, Muzan would never hurt him. There is no one left, but him. 

Which isn’t far from the truth.

He did murder his entire family in front of him and only kept him alive as a demon, but not that Tanjiro could remember and he'll keep it that way.

When the boy first regained consciousness and saw him, he was such an obstinate, confused, and mad little thing. Spitting fiery words of insults and threats at him; while futility struggling to fight him tooth and nail.

There had been moments when the boy's defiance had been cute like a small kitten trying to act ferocious and other times it had been exceedingly vexing.

Rewarding Tanjiro when he did complied and punished when he didn't. It was similar to training an animal. 

There is no point in fighting. The moment a human is exposed to his blood, they belong to him.

There is no return.

Naturally, Tanjiro does not remember much of his human life when he became a demon.

However, in the beginning, there were moments when Tanjiro would recall parts of his human life. It ways easy to notice when the boy would have an episode. It became a song and dance they played so often. His eyes would go wide, movements falter, words become incoherent, an expression of confusion flashes, and then an aura of the animosity radiates off the boy.

He has spent most of his time pretending to play human and he had no qualms comforting (manipulating) the boy.

In a soft tone, he whispers down towards the boy’s ear, his sweet
words laced insidiously with poison. “Shh, there is nothing to fear Tanjiro.
It’s nothing more than a bad dream.”

His hand gently strokes the boy’s  face, from his scar and down to his cheek.

He cradles the trembling child into his arms and lulls him to a (false)
peaceful slumber.

Like a child who had a nightmare.

Now Tanjiro understands his place better and will come when he calls for him. However, he doesn’t know if it's in the boy’s nature or an unconscious response to resist him. Tanjiro does not actively oppose him, but there are instances of disobedience and hesitation in following his order.  The boy questions him like an uncertain and innocent child.

As if he, Muzan can be wrong in his decisions.

“Just how long do you plan to sleep?” Muzan scowls and more annoyed at the fact that a mere child was forcing him to wait.

He’s been contemplating for three days now at how he’ll punish Tanjiro for sleeping for this long. He allowed no such thing. Killing the boy is out of the question as it would be such a merciful thing to do for the boy and not to mention, it would be counter intuitive. If the boy wants to sleep then he would be giving him an eternity to sleep.

As he said moments ago: There is no escape from him and even if there was a way, he won’t make it easy. 

He knows Tanjiro still refuses to devour humans and sleeps to recover his strength; despite all the threats and punishments.

This grates on his nerves.

But patience is key and he, Muzan, is a very patient person... and also very generous.

He rose from his chair and languidly stalks towards their meal tonight, an unconscious young woman on the floor. She didn’t even stir as he lifts her to bite her neck, it was as if she was sleeping like the dead.

He didn't give her too much of that sleeping concoction he prepared, now did he? He must have been too concerned with the fact he didn’t want her to wake the sleeping child up.

Though, the blue spider-lily is essential to his goal, that did not mean Muzan didn’t try to achieve perfection through other methods. There have been several experiments through the use of drugs, herbs, and other chemical components.

When all is done, he throws the human away, letting her bleed to death for all he cares and walks towards the bed. He cups Tanjiro’s face gently and leans down to press their lips together; filling the boy’s mouth with the sweet liquid.

He watches Tanjiro jolt awake and hands fly to his shoulder in an attempt to push him away. However, the panic quickly dissipates and the last bit of control (humanity) is overcome by his demonic urges.

How beautiful his eyes looked dyed scarlet… just like a red spider-lily.

He smirks at the boy’s eagerness, lapping ever drop of blood in his mouth and hands, unconsciously pulling their bodies closer to each other. When they parted, there was something so mesmerizing about the way Tanjiro’s cheeks flushed with a disappointed expression.

As if he wanted more.

Any demon who knew there place, understood no one demanded anything from him, Muzan. However, it was somewhat pitiful to see the torn expression of desire, self-control, and shame on the boy’s face.

Honestly, how could he deny him?

Tanjirou pants his name desperately in need of something, but it was obvious that the boy did not know what. He watches as the boy nuzzles his face towards the palm of his hand as if offering himself, pleading for guidance.

A shiver runs down his spine.

“Learn well, Tanjiro. I expect you to please me next time.”

Ruby eyes glimmering brightly at him and for some odd reason, he wonders…how close can he get to the sun without burning him?