Muzan Kibutsuji (鬼舞辻 無惨 きぶつじ むざん) is the progenitor of the demons in Demon Slayer. Here are 14 cruel quotes the Brutal demon king left. All the quotes are written in Japanese including romaji and translated in English.

1.

私 (わたし) のことを誰 (だれ) にも喋 (しゃべ) ってはいけない
Koyoharu Gotoge『Demon Slayer vol.2』
喋 (しゃべ) ったらすぐにわかる……
私 (私) はいつも君 (きみ) を見 (み) ている
Don’t tell anyone about me. I can tell if you do right away……I have my eyes on you all the time.
Watashi no koto wo dare nimo shabettewa ikenai Shabettara sugu ni wakaru…… Watashi wa itsumo kimi wo miteiru
To Numa no Oni (沼の鬼 ぬまのおに)
Numa no Oni got extraordinarily scared when Tanjiro asked him about Muzan. We can tell Muzan is extremely frightening for demons.
2.

頭 (こうべ) を垂 (た) れて蹲 (つくば) え
Koyoharu Gotoge『Demon Slayer vol.6』
平伏 (へいふく) せよ
Head down and kneel. Prostrate before me.
Koube wo tarete tsukubae Heifuku seyo
To the Lower Moon Demons
Muzan gathered the Lower Moons to his base, Mugenjo (無限城 むげんじょう). They stiffed their bodies by hearing Muzan’s voice. For them, Muzan is the absolute existence they could never resist.
3.
お前 (まえ) は私 (わたし) に指図 (さしず) した
Koyoharu Gotoge『Demon Slayer vol.6』
死 (し) に値 (あたい) する
You told me what to do. You deserve death.
Omae wa watashi ni sashizu shita Shi ni atai suru
To Rokuro (轆轤 ろくろ), the Lower Moon Rank 2
Demons are not allowed to deny what Muzan says or speak their suggestions. Moreover, Muzan can read what demons are thinking. And if he doesn’t like them… They deserve death.
4.

猗窩座 (あかざ) 猗窩座 (あかざ)
Koyoharu Gotoge『Demon Slayer vol.8』
猗窩座 (あかざ) !!
お前 (まえ) には失望 (しつぼう) した
Akaza, Akaza, Akaza!! I disappointed in you.
Akaza Akaza Akaza!! Omae niwa shitsubou shita
To Akaza
Muzan never gets satisfied with just defeating one Hashira. According to the official fan book 1, Akaza is Muzan’s favorite. But even for Akaza, it is not easy to satisfy his autocratic boss.
Interested in Akaza’s quotes? See my article → 28 Cruel but Sad Quotes of 12 Moon Demons in Japanese from Demon Slayer
5.
私 (わたし) が嫌 (きら) いなものは“変化 (へんか)”だ
Koyoharu Gotoge『Demon Slayer vol.12』
What I hate is “change”.
Watashi ga kirai na mono wa “henka” da
To the Upper Moon Demons
Muzan was mad about one of the Upper Moons had been defeated by the Demon Slayer Corp. He gathered the rest of the Upper Moons and ragged on them.
6.
私 (わたし) には何 (なん) の天罰 (てんばつ) も下 (くだ) っていない
Koyoharu Gotoge『Demon Slayer vol.16』
何百何千 (なんびゃくなんぜん) という人間 (にんげん) を殺 (ころ) しても私 (わたし) は許 (ゆる) されている
この千年 (せんねん) 神 (かみ) も仏 (ほとけ) も見 (み) たことがない
I haven’t got any punishments. I have been forgiven for killing hundreds of thousands of humans. I haven’t seen God or Buddha for thousand years,
Watashi niwa nan no tenbatsu mo kudatte inai Nanbyaku nanzen to iu ningen wo koroshitemo watashi wa yurusarete iru Kono sennen kami mo hotoke mo mitakoto ga nai
To Kagaya Ubuyashiki (産屋敷 耀哉 うぶやしき かがや)
What Muzan said to Oyakaya sama (Ubuyashiki) at the Ubuyashiki’s mansion. Muzna has killed so many innocent people and turned lots of helpless people into demons. But, it seems Muzan doen’t feef a bit of guilty.
7.

これで私 (わたし) を追 (お) い詰 (つ) めたつもりか?
Koyoharu Gotoge『Demon Slayer vol.16』
貴様 (きさま) らがこれから行 (い)くのは地獄 (じごく) だ‼
Do you think you’ve chased me down? You are going to the hell from now!!
Kore de watashi wo oitsumeta tsumori ka? Kisamara ga korekara ikuno wa jigoku da!!
To the Demon Slayers
The Demon Slayers succeeded in restraining Muzan’s body temporarily. But then, they sall fell into Muzan’s base, Mugenjo (無限城 むげんじょう).
8.
鬼 (おに) となれば無限 (むげん) の刻 (とき) を生 (い) きられる
Koyoharu Gotoge『Demon Slayer vol.20』
If you become a demon, you can live forever.
Oni to nareba mugen no toki wo ikirareru
To Michikatsu Tsugikuni (継国 厳勝 つぎくに みちかつ)
Michikatsu Tsugikuni is the name of Kokushibo (黒死牟 こくしぼう) the Uppe Moon Rank 1, when he was still a human. He was a good swordman but made a sad choice because of his background.
Kokushibo’s quotes are here → 28 Cruel but Sad Quotes of 12 Moon Demons in Japanese from Demon Slayer
9.

誰 (だれ) も彼 (かれ) も役 (やく) には立 (た) たなかった
Koyoharu Gotoge『Demon Slayer vol.21』
鬼狩 (おにが) りは今夜 (こんや) 潰 (つぶ) す
私 (わたし) がこれから皆殺 (みなごろ) しにする
Nobody was useful. I will smash the demon hunters tonight. I will kill them all.
Dare mo kare mo yaku niwa tatanakatta Onigari wa konya tsubusu Watashi ga korekara minagoroshi ni suru
To himself
It seems that the captain of demons is totally different from the one of the Demon Slayer Corp.
If you are interested in the captain of the Demon Slayer Corps, Ubuyashiki, you can read his quotes →23 Inspirational Quotes in Japanese From Demon Slayer
Notes: 鬼狩 (おにが)り →demon hunters. Demons usually call the Demon slayer Corp so instead. I think that’s because the Demon Slayer Corp is the name human had made.
10.
死 (し) んだ人間 (にんげん) が生 (い) き返 (かえ) ることはないのだ
Koyoharu Gotoge『Demon Slayer vol.21』
いつまでもそんなことに拘 (こだわ) ってないで日銭 (ひぜに) を稼 (かせ) いで静 (しず) かに暮 (く) らせば良 (よ) いだろう
Dead people never come alive. Why don’t you just work for dairy money and live quietly instead of sticking to such things?
Shinda ningen da ikikaeru koto wa nainoda itsumademo sonna koto ni kodawatte naide hizeni wo kaseide Shizuka ni kuraseba yoidarou
To Tanjiro
Muzan’s cold word insulted his victims and the families, and it enraged Tanjiro.
11.
つまらぬ小細工 (こざいく) ばかりするな‼
Koyoharu Gotoge『Demon Slayer vol.22』
蠅共 (はえども) が‼
Don’t play cheap tricks!! Flies!!
Tsumaranu kozaiku bakari suruna!! Hae domo ga!!
To the Demon Slayers
Muzan got irritated by the Demon Slayers because they kept attacking him by all possible means.
12.

醜 (みにく) い姿 (すがた) だ
Koyoharu Gotoge『Demon Slayer vol.22』
これではどちらが鬼 (おに) か分 (わ) からないな 竈門炭治郎 (かまどたんじろう) ……虫酸 (むしず) が走 (はし) る
You look Ugly. Now we can’t tell which one is a demon, Tanjiro Kamado. You make me sick.
MInikui sugara da Kore dewa dochira ga oni ka wakaranai na Kamado Tanjiro...... Mushizu ga hashiru
To Tanjiro
Tanjiro got serious injury, but he still stood up to confront Muzan. Facing the young Demon Slayers, Muzan started feeling in awe of him.
13.
本当 (ほんとう) の化 (ば) け物 (もの) はあの男 (おとこ) だ
Koyoharu Gotoge『Demon Slayer vol.22』
私 (わたし) ではない!!
The true monster is that man. Not me!!
Hontou no bakemono wa ano otoko da Watashi dewa nai!!
In his mind
Through the fierce battle, Muzan saw “that man” in Tanjiro; Yoriichi Tsugikuni (継国 縁壱 つぎくに よりいち) who had almost killed Muzan hundreds of years ago. “That man is still chasing me.” He must have been scared.
14.

鬼狩 (おにが) りという組織 (そしき) が数珠繋 (じゅずつな) ぎとなって
Koyoharu Gotoge『Demon Slayer vol.22』
それ自体 (じたい) がひとつの生 (い) き物 (もの) のように私 (わたし) を絡 (から) め取 (と) らんとしている
The organization of demon hunters connects to each other to become like one creature, and it about to capture me.
Onigari to iu soshiki ga juzutsunagi to natte sore jitai ga hitotsu no ikimono no youni watashi wo karametoran to shiteiru
In his mind
Once Muzan had denied what Ubuyashiki said in the Ubuyashiki’s mansion, he, at last, understood the captain of Demon Slayer Corp was right.
If you want to read more Demon Slayer Quotes;
Shinobu Kocho →10 Impressive Quotes Of Shinobu Kocho In Japanese And English From Demon Slayer
Giyu Tomioka→ 9 Inspirational Quotes of Giyu Tomioka in Japanese and English from Demon Slayer
Tanjiro Kamado → 13 Best Quotes Of Tanjiro Kamado In Japanese From Demon Slayer
Hatshira → Remaining Quotes Of Hashira In Japanese From Demon Slayer
12 Moon Demons → 28 Cruel but Sad Quotes of 12 Moon Demons in Japanese from Demon Slayer
and more! → 23 Inspirational Quotes in Japanese From Demon Slayer