Enmu

Enmu was a member of the Twelve Demon Moons, having held the position of Lower Moon One.

Personality
Enmu is very sadistic and enjoys the pain and suffering of humans with his most favorite method being giving them a happy and pleasant dream before turning it into a nightmare. Like all Demons,Enmu has shown to have little to no care for human life seeing as he uses as nothing more than mere pawns and does not bother to warn them of the various dangers of facing demon slayers and simply considered them to be expendable,he also seems to revel in turning humans into his desperate servants by using his power to give them nice and pleasant dream before pulling them out and falsely promise to give them more if he helps him. Enmu has also shown to be intelligent and cautious,having complete understanding of his powers strengths and weaknesses and made sure to both exploits and avoid them in order to succeed,However upon being given more blood and being further empowered by Muzan, Enmu seemed to have become overconfident,arrogant and greedy,as seen when he began to act more recklessly in order to obtain more blood in order to properly challenge one of the Upper Moons to a blood duel and take their place as an Upper Moon.

Functional Recovery Training Arc
Having been summoned to a meeting of the six Lower Moons, Enmu entered the room of winding staircases with his fellow Demons. They were then confronted by a feminine-looking Kibutsuji Muzan, who demanded that they prostrate themselves, which Enmu quickly obeyed. He remained silent as his leader berated all of them for being too weak, with Muzan citing the death of Lower Moon Five, Rui, as his example.

Demon Train Arc
Enmu remained silent as Lower Moon Six was brutally killed by Muzan after being eaten alive, with almost no reaction as Lower Moon Four was subsequently slaughtered similarly to Lower Moon Six. He thought his comrade Lower Moon Three a fool as the latter panicked and attempted to flee, only to also be slain by their leader. He then listened as Lower Moon Two tried to convince Muzan of his usefulness, only for his efforts to inevitably fail to keep him alive. When asked for his final words, Enmu expresses joy at Muzan killing him personally and for the suffering of humans and his fellow Moons, thanking his leader for leaving him until last. He is then stabbed by a needle-like appendage and given some of Muzan's blood, along with the orders to kill the Demon Killing Corps' Pillars and Kamado Tanjirou. Rolling around on the floor in agony, Enmu nevertheless laughed, Muzan's promise for more blood the only thing on his mind.

Later, he stood upon the steam engine, remarking that dying while dreaming is a blessing. One of Enmu's hands spoke with the train's conductor about the success of putting the Demon Hunters to sleep and did the same to him. It then addressed the other conspirators, cautioning them about how to proceed with their plan and of its host's temporary inability to move. Back on top of the train, Enmu's main body reflected on his plan to destroy his targets' spirit cores, rendering them completely vulnerable, and of the fragile nature of human hearts. As his plan began to unfold, he noted his victims' inability to wake up and stop his twisted scheme.

Enmu then noticed that his human pawns were having trouble destroying the spirit cores, but noted that it was alright as they were simply buying time. Shortly thereafter, he turned as Kamado Tanjirou approached him, greeting him and stating that he showed him a pleasant dream, but could have made it a nightmare. Smiling, the Sleep Demon then told Tanjirou that his next dream would be of his father coming back to life.

Enmu mused over his enjoyment of first showing humans pleasant dreams and then giving them nightmares, as well as the finer details of his plan, but also wondered how Tanjirou had figured out how to wake himself so quickly. He then noticed the Demon Hunter's earrings, much to his joy, his thoughts solely on receiving more of Muzan's blood and challenging the Upper Moons with his newfound strength. An enraged Tanjirou attempted to attack the Lower Moon, but Enmu quickly put him to sleep. The youth just as quickly broke Enmu's technique, despite the Demon's multiple attempts, leading the surprised Lower Moon to compliment his determination. His neck was then severed by the furious Demon Hunter, but an unfazed Enmu merely stated that he now knew why his leader had wanted Tanjirou dead, and revealed to the shocked youth the reason for his continued survival: he had fused with the train while they had all slept. Taunting Tanjirou to protect the two hundred passengers inside of him, Enmu's severed head merged into the train.

Thanks to Tanjirou and Inosuke joint effort, they manage to discover Enmu head and subsequently, behead him by completely cutting off the train's top engine compartment,Enmu being in complete disbelief at his failure began to curse all the demon slayers, Nezuko and the Upper Moon due to being inferior to them in power,as his body was slowly disintegrating,he attempted to at least kill the weakened Tanjiro and Inosuke but only failed once more as his body began to crumble faster,as he died Enmu began to further curse his failure and began to frantically think that the entire debacle to be a nightmare and demanded to have redo as he finally crumbled to nothing.

Demon Abilities
As Lower Moon One,Enmu was the strongest lower Moon and closest to matching the strength of the Upper Moons and upon receiving more Blood from Muzan his power and abilities were further enhanced.
 * Regeneration - Like all Demon Enmu has powerful regenerative abilities and due to being one of the lower moons its likely his self healing was above that of average demons.
 * Sleep Tickets - By mixing in his blood with ink on train tickets,Enmu can put anyone who held them to sleep,thus making them vulnerable to his powers.
 * Assimilation - Enmu also displayed the ability to absorb and incorporate himself into large inanimate objects,seeing as how he managed to assimilate himself into something as large as a train and transform it into his main body and was planning on eating and assimilating over 200 hundred passengers on his new train body.
 * Flesh Detachments - Enmu has also shown the ability to create flesh detachments from his own flesh and blood,being able to create and detach one of his own hands and send it out independent from his main body and later upon being given more blood from Muzan,He was able to create a detachment as large as a human body in order to fool others into thinking that it was his real body.

Blood Demon Technique:Enmu's Main ability is his power to enter,manipulate and control someones dreams and is even capable of killing someone by destroying their "Spiritual core" effectively destroying their mind,but not their bodies,additionally their is the danger of being affected and possibly mentally changed by the unconscious mind as such Enmu instead has someone else enter into his targets dream in his stead,as seen when the human sent into Tanjiro dream was affected by his natural kind spirit and lost the will to kill him.
 * Compelling Hypnotic Whisper (のき) - A mouth forms on his hand, who tells the target to sleep and the target falls asleep.
 * Coerced Swooning Sleep: Eyeballs (・き) - Enmu creates multiple eyes on which is written "Dream" and upon looking into them, the target falls asleep.

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