Doma just smirked at Inosuke's claims. 

Doma: You were raised by boras, but you have a way with words. However, you seem to have some misconceptions. 

Inosuke: And what exactly are those mis ... miscon ... miscontraptions? 

Weiss: Misconceptions, Dumbass. He means you're mistaken about something. 

Doma: Yes, we have a smart one and cute one here. What I mean to say is that heaven and hell don't exist. They're nothing but fantasies, fairy tales. 

Weiss: And why do you say that? 

Doma: In reality, humans who live virtuously and decently suffer irrational tragedies. While evil people do what they want. Because they live insane, interesting lives and drink sweet nectar. Since these people are not getting their divine punishment, at the very least they'll go to hell when they die. That's what mentally weak people have to think, or they wouldn't be able to live with themselves, right? They keep it deep in their minds. I swear, humans are so pitiful. 

Inosuke: JUST SHUT THE FUCK UP! IF THERE ISN'T A HELL THEN I'LL JUST MAKE ONE! DON'T TALK ABOUT MY MOM LIKE SHE WAS UNHAPPY, YOU DEMON BASTARD! 

Doma: BLOOD DEMON ART: FROZEN CLOUD! 

Kanao: INOSUKE LOOK OUT! IF IT TOUCHES YOU YOUR BODY WILL- 

Inosuke: BEAST BREATHING: TENTH FANG: CIRCULAR FANGS! 

He used his blades like fans and blew the frozen mist away! 

Weiss: That was ... surprisingly smart of him? Is it like Luffy where he uses his brain in battle? 

Doma: How interesting. If it's possible, I can keep this up until I get bored. But unfortunately, I don't have time anymore. You can play with them instead. BLOOD DEMON ART: CRYSTAL MIKO! 

He created ice duplicates of himself. 

Weiss: Wait, he can make ice clones like me? 

Inosuke: PBTH! That's stupid! Like that will- 

Ice Doma: BLOOD DEMON ART: SCATTERED LOTUSES! 

Weiss: OH COME ON! 

All three of them were slicing at the ice petals. 

Weiss: They're- 

Kanao: They're just as strong as his! 

Doma: Yes, my ice clones are as powerful as mine. Now, I think I'll go. 

He began to lave. 

Inosuke: COME BACK HERE YOU COWARD! 

They started to use all of his techniques, from the ice lotus flowers to the ice princesses, and the ice lotus vines! 

Weiss: If we don't do something soon, he's going to escape! 

Kanao: We can't let him do that! 

Doma: If you're getting lonelier, I have more. 

He sent out five more! 

Weiss: I HATE THIS GUY! ICE BREATHING: ICE DRAGON! 

She created an ice dragon and took down one of the clones! 

And then suddenly, Doma began to feel weak. 

Doma: Wh-What? 

His face was melting. 

Doma: What's going ... on? 

Shinobu: Heh, I got you. 

Everyone turned to Shinobu as she got up. 

Doma: What did- 

Shinobu: Remember when you grabbed me and tried to have your way with me? At that moment, I injected a powerful poison into your body. This poison will destroy your body from the inside. 

The ice clones began to shatter. I knew I wouldn't be able to kill you. I was just buying time for Kanao and the others to get their chance. 

Weiss: Then that means- 

Kanao: NOW'S OUR CHANCE! 

Weiss, Kanao, and Inosuke charged at Doma! 

Inosuke: DIE YOU ASSHOLE! 

Doma: NOT YET! IT'S NOT OVER YET! BLOOD DEMON ART: HOARFROST LILIY BODHISATTVA! 

He summoned a giant Ice Buddha Statue! 

It then slammed down on the ground with Weiss grabbing Shinobu! 

Kanao then realized it. 

Kanao: It looks like his precision has dropped. This is a desperate pitch, but this is the last thing left. 

Her eyes then turned red. 

Kanao: FLOWER BREATHING: FINAL FORM: SCARLET SPIDER LILY EYES! 

She dodged the attacks perfectly and while her body was becoming icy, she charged at Doma, and then- 

Weiss: OH NO YOU DON'T! ICE BREATHING: EIGHTH FORM: ICE AGE!!! 

She slammed her Nichirin Blade into the ground and it created giant ice spikes, trapping the Ice Buddha in place! 

Weiss: NOW KANAO! CUT THIS FUCKER'S HEAD OFF! 

Kanao's blade reached Doma's neck, but her arm was getting stiff! 

Inosuke: SHIT! HERE! BEAST BREATHING: BRAND NEW IDEA: THROWING SLICE! 

Inosuke threw his two blades at Kanao's sword and then Doma's head went flying off his body! 

Doma: I ... lost? To this ... weakling? To a Poison User who I can't even call a swordsman? To this girl who probably has never even faced an Upper Moon before. And to a guy who doesn't even have the foundation for swordsmanship? I don't know ... I can't give up yet. I might not die. Like Lord Muzan and Lord Akaza. 

But his body began to crumble away. 

Doma: I don't feel anything. I remember when my Father kept putting his hands on female adherents, my mother stabbed him to death. And then she killed herself afterwards. When that happened, I wasn't a demon back then. And yet I didn't even feel a thing. When I turned twenty, that's when Lord Muza came to me, and he turned me into a demon. I have lived over 100 years, but in the end, it seems like emotions don't mean a thing. 

And then Shinobu stomped on his remains. 

Shinobu: Rot in hell, Shithead. 

Weiss: Looks like, we finally did it. 

She then saw Inosuke crying. 

Weiss: (Sigh) Hey, I'm sure your mother loved you a whole lot. And she's proud of you where you ar- 

He hugged her. 

Inosuke: Weiss, thanks. 

Weiss: Anytime, my friend. 

Kanao on the other hand was helping Shinobu walk. 

Shinobu: Are you alright Kanao? 

Kanao: I'm sorry Shinobu. 

Shinobu: What do you have to be sorry about? 

Kanao: When Kanae died. I didn't cry. You all were crying, but I didn't. And it really bugged me. Yet, you didn't criticize me for it. You all were so kind to me. When you cry, you get kicked on and stepped on. You get dragged around and dumped into water. You have to watch what you do, or something bad will happen. Back then I saw several of my brothers' bodies felt cold. I'm sure that's why I stopped being able to cry. I'm sorry. 

Shinobu just hugged her sister. 

Shinobu: It's alright Kanao. If you need to cry, I'm here for you. 

And with that, Kanao cried into her sister's chest while Weiss continued to comfort Inosuke. 

Weiss: He may be a massive idiot, but he's also like a child who lost his mother. 

Meanwhile... 

You, Tanjiro, and Giyu saw another crow come by. 

Crow: CAW CAW! CAW CAW! Shinobu, Weiss, Kanao, and Inosuke, they have defeated Upper Moon 2! 

(Y/N): HOLY CRAP! They actually did it! 

Giyu: One by one, the Upper Moons keep falling. 

Tanjiro: That means we're getting closer and closer to- 

(Y/N): Muzan. 

At the same time... 

Obanai and Mitsuri found Nakime with her hair sticking to a wall. 

Mitsuri: Mr. Iguro, she must be Upper Moon 4! 

Indeed, Nakime now had the Upper Moon 4 Kanji on her eye! 

Obanai: (L/N) said that Upper Moon 4 was a small man with a hideous face. She must be his replacement. 

Mitsuri: Then let's take her down! I have to give it my all! 

Mitsuri went to go and attack, but a wall came up and knocked her back! 

Mitsuri: AAAAAAAAAGH! 

Obanai then got her to safety. 

Obanai: Kanroji, we don't know what our opponent can do. You need to be calm and think. 

Mitsuri: S-Sorry about that. 

Just then they almost fell into a room. 

Mitsuri: WHOA! 

They hopped to safety as more doors opened. 

And then rooms shot out like columns and nearly hit them! 

Mitsuri: LOOK OUT MR. IGURO! 

Mitsuri slashed them down with her sword! 

Mitsuri: It looks like she can control this whole place! 

Nakime continued to play her biwa and as Mitsuri tired to cut her head off- 

Mitsuri: AAAAAAAAAAAAAGH! 

She fell into a room. 

Obanai: DAMN YOU! SNAKE BREATHING: SECOND FORM: SMALL SNAKE'S POISON FANG! 

However, he was knocked back as well. 

At the same time... 

Blake, Yang, Muichiro, and Gyomei moved throughout the Infinity Castle, although one of the room columns hit Blake and Muichiro! 

Blake: WHAT IN THE?! 

Muichiro: WHAT'S GOING ON?! 

Yang: BLAKE! 

Gyomei: TOKITO! 

Blake: JUST KEEP GOING! 

Muichiro: DON'T WORRY ABOUT US! 

The Cat Faunus and the Mist Hashira fell into a room which seemed like a maze! 

???: Well well, I have two Demon Slayers to play with. 

Blake: This aura ... it- 

Muichiro: Blake, that man he's- 

Blake: Yes. He's- 

It was Kokushibo. 

Blake and Muichiro: Upper Moon One. Muzan's right hand man.