---
title: 'Demon Slayer: Infinity Castle ENDING EXPLAINED + What''s Next'
source: 'https://youtube.com/watch?v=NWL8wG3HH4w'
video_id: 'NWL8wG3HH4w'
date: 2026-06-15
duration_sec: 0
---

# Demon Slayer: Infinity Castle ENDING EXPLAINED + What's Next

> Source: [Demon Slayer: Infinity Castle ENDING EXPLAINED + What's Next](https://youtube.com/watch?v=NWL8wG3HH4w)

## Summary

This video breaks down the plot and key character matchups of Demon Slayer: Infinity Castle Part One, explaining the Ubayashiki family curse, the backstories of Upper Rank demons Doma and Kaigaku, and the central rivalry between Tanjiro and Akaza. It also sets up future battles for the rest of the trilogy.

### Key Points

- **Movie Title and Structure** [0:14] — The movie is officially titled 'Demon Slayer: Infinity Castle Part One, Akaza Returns' and is the first part of a trilogy serving as the series finale, likely covering both the Infinity Castle and Sunrise Countdown arcs.
- **Ubayashiki Family Sacrifice** [0:53] — Kagaya Ubayashiki, his wife Amane, and two daughters sacrifice themselves to trap Muzan, leaving three surviving children (Kiriya, Kuina, and Kanata) to map the Infinity Castle and aid the Demon Slayers.
- **Doma's Backstory and Fight** [2:39] — Doma, Upper Rank Two, was a cult figurehead who became a demon at 20 and ate his disciples. He kills Shinobu, and her apprentice Kanao faces him, symbolizing the contrast between apathy and human will.
- **Kaigaku's Betrayal** [5:31] — Kaigaku, Zenitsu's former fellow disciple, becomes a demon to save himself, leading to a fight where Zenitsu defeats him with a new Thunder Breathing technique, honoring their master.
- **Akaza's Return and Rivalry** [7:31] — Akaza returns to fight Tanjiro and Giyu, mirroring his previous battle with Rengoku. Tanjiro uses Sun Breathing and the transparent world, while Akaza's backstory reveals his tragic past and eventual suicide for an honorable death.
- **Future Battles Setup** [10:06] — Remaining matchups include Kanao vs. Doma, Inosuke in the changing halls, Tokito vs. Upper Moon One (likely), and Obanai and Mitsuri fighting together, with all plotlines continuing in Part Two.

### Conclusion

The Infinity Castle arc sets up intense battles and character resolutions, with the trilogy promising a complete conclusion to the Demon Slayer series.

## Transcript

Hey, welcome back to Screen Crush. I'm
Ryan Ary and this is The Demon Slayer:
The Infinity Castle Broken Down and
explained. Now, we're not going to go
into too much on the manga after this
movie's events, but spoilers for
Infinity Castle are ahead. So, let's
dive in. First of all, this movie is
officially titled Demon Slayer Kametsu
Noa: The Movie Infinity Castle Part One,
Akaza Returns. So, it's only the first
part in a trilogy that serves as a
finale to the series. Technically, the
Infinity Castle arc is the pen ultimate
arc in the series. The final being the
Sunrise Countdown arc, although we're
still unsure. Most likely, this trilogy
released in theaters will encompass both
arcs and fully conclude the Demon Slayer
series. Now, Infinity Castle continues
many plot lines that were sprinkled
throughout the show since season 1. In
the anime, these plot lines were either
really vague or barely touched upon, so
honestly, it could be pretty confusing
going into the movie full throttle. So,
let's start with the Ubayashiki family.
The movie begins with the Demon Slayers
falling through the Infinity Castle. all
the hashira more and Kaiga Ubayashiki,
the previous master of the core. The
master finally came face tof face with
man at the end of the last arc, which by
the way we covered completely in our
recap video. You should watch it. It's
very good. He explains the Ubayashiki
curse that arose from having a demon
born from the family.
>> A demon has recently emerged from your
family's bloodline. Commit yourselves
from here on out to eliminating that
manifestation. Even after centuries of
marrying the daughters of priests,
anybody with the name Ubayashiki doesn't
live past age 30. The only thing that
will save them is defeating Muzan.
Finally turning the tide in this fight,
the Ubayashiki family makes a drastic
move.
Kagaya, his wife Ammane, and two of
their daughters agree to sacrifice
themselves in order to trap man for the
demon slayers. Now, this leaves us
thinking the Ubayashiki family is no
more. But as we see in Infinity Castle,
there are three still living children,
Kira, Kuina, and Kaneta. The three kids
map out the Infinity Castle, aiding the
rest of the Demon Slayers and trying to
predict where man is hiding. At the
forefront is Kira. He's one of five kids
and the only son of Kagaya and Amane.
With Kagaya's passing, he is the next
master of the Demon Slayer Corps. Now,
we've actually seen Kira before back in
season 1 during Final Selection.
>> You've come to enter the Demon Slayer
Cor's final selection. At that time, he
dressed more feminine. Now, this is most
likely because dressing as a girl would
have helped disguise his identity as the
potential next heir of the core and lead
to fewer demon attacks on the Ubayashiki
family. Teaming up with the benevolent
demons, the Ubayashiki siblings use
Yushiro's blood art on the communication
crows to locate all the slayers and
remaining demons. So, this leads us
straight into the fight with Doma.
>> I see.
>> Back in the Entertainment District arc,
we saw Doma as the previous upper rank
six, giving blood to Guutaro and Daky.
Maybe you'll be a 12 kizaki like me.
>> Rising to upper rank two, Doma has shown
his prowess at killing.
>> Has there ever been a time I didn't meet
your expectations, my lord?
>> And an airy tieress much to the chagrin
of the rest of the upper ranks.
>> And man himself,
>> keep your wretched eyeballs. I have no
need for them.
>> His status as a cult leader was also
nodded to at the beginning of the
swordsmith village arc.
>> Your disciples have just arrived. But we
dive deeper into his backstory in the
Infinity Castle. Born to leaders of the
Eternal Paradise faith, baby Doma was
made into the cult's figurehead.
Disciples would ask the child leader for
advice and blessings on money, love, and
other life struggles. Due to his apathy
and confusion for human emotions, Doma
found these pleasor and delusional. When
he turned 20, man offered him blood, and
Doma became a little freak who liked
eating people. His new mission in the
cult was to eat his disciples, convinced
that it would help them end their
suffering and enter paradise. Now, this
is what he tells Shaneobu before killing
her and absorbing her into his body.
>> No, I'm still sad. It didn't work.
>> Shobu's apprentice, Kana, makes it just
in time before seeing her mentor give a
final signal and perish, leaving Kana to
face off against Doma. Now, this is an
interesting matchup for several reasons.
Not only is it because of the symbolism
of a girl avenging her adopted sisters
against a demon who primarily feeds on
women, but it's also their experience
with emotion or lack thereof. Both Doma
and Kau have lived apathetic lifestyles.
Like we saw in season 1, Kana grew up in
an abusive household and repressed her
emotions to the point of dissociating as
a defensive mechanism.
>> But then one day,
I heard a snapping sound and I never
knew pain again. She was unable to make
decisions by herself until she met the
Coocho sisters.
>> Next time you're on your own, flip this
coin to help you make a choice.
>> Similar to the Comedo siblings, Kana
could have become a demon just like Doma
if things had worked out just a little
differently. The key difference leading
to their diverging paths are, like the
previous master said, the sense of
entitlement and human will. Even as a
kid, Doma had the world at his feet and
believed everyone to be dim-witted
because of their hope for a better life.
Aside from man, he always had a
condescending heir when speaking to
anyone. Conal, on the other hand, came
from nothing, not even a name.
>> She doesn't have a name. All right. She
never got one.
>> It was through her time with the Coach
siblings, the butterfly girls, and
Toniro, that she slowly began to gain
back her will and passion.
>> Tonerro is asleep, so please be quiet.
You need to hang on tight. A lot of what
makes up these upper ranked demons are a
sense of entitlement or the idea of
unearned power without consequences.
This is especially true to the next
demon we see, Kaaku, the new upper Moon
6. Now, we first saw Kaaku in season 1
during Zenitzu's backstory.
>> Any effort spent on you is an absolute
waste of time.
>> Ever so brash and cruel, Kyaku would
admonish Zenitsu for being so outwardly
cowardly and resent the fact that their
thunderbreathing master deemed them both
to be his successors. Despite Zenitu not
being able to complete all the breathing
techniques, but as much as he boasted
about his strength, Kagaku was
internally extremely spineless and
selfish. In the letter from the Hashira
training arc, Zenitzu finds out that
their thunderb breathing master
committed sepeku due to his students
choice to become a demon. When offered
blood from Upper Mood 1, Kaiaku
immediately bowed to his strength,
turning back on humanity to save his own
skin. Now, this shouldn't be news to us
because we have seen him act in this
self-s serving way before. In the
Hashira training arc, during Guiome's
backstory, we actually see Kyaku as one
of the children in his orphanage. After
being caught stealing from the temple,
Kyaku runs into a demon and surprise
surprise, offers up the other orphans
and Guiome to save his own skin. So,
this leads to a massacre at the temple
and Guiam, falsely imprisoned for
murder.
>> But these are children we're talking
about. All they can do is think of
themselves.
>> Zenitsu and Kyaku's face off really
demonstrates the inverse nature of these
two characters. Kyaku's outward
arrogance and audacity masks his frail
principles and timid heart. While
Zenitsu's notable cowardice doesn't
overpower his perseverance and loyalty
to his loved ones, until he became a
demon, Zenitzu always regarded Kigaku as
an older brother, no matter how cruel he
was to him.
>> Good for nothing. Any effort spent on
you is an absolute waste of time.
>> Zenitzu defeats Upper Moon 6 with a new
thunder breathing technique, bringing
pride to his teacher. Yiro administers
first aid to Zenitu. Now, you'll notice
that he's now dawning a demon slayer
uniform. Yhiro is still the only demon
to be created by Lady Tamio and has no
ill intention. To maintain his safety,
he now blends in with the rest of the
core, hiding his demon status and
prioritizing healing the rest of the
core members. So, this leads to the next
major upper rank fight. Now, like the
title suggests, this movie mainly
focuses on the return of Aza and his
rivalry with Tano. For a quick
refresher, Aaza was the upper ranked
demon who showed up at the end of the
Mugan Train arc. His last fight with
Reng Goku was when the other flame
Hashira denied his offer to be a demon
and made his final stand. This urges
Tano to call out his fear of the sun and
demon slayers. After being bered by
Muzan, Akaza pummel the sword Tano shot
at his neck and vows to make him pay.
>> I'm going to save her tearing you limb
from limb.
>> While reuniting with Taniro and beating
Guillu, the water hashira, Akaza
suggests Guillu to become a demon.
Making the same offer that he did to Ren
Goku. Obviously denying this offer, the
three prepare for a showdown. Now, while
fighting, we can see just how much of
Ring Goku's spirit is reflected in Tano,
becoming a mirror of Akaz's previous
fight with the flame Hashira.
>> It is the duty of those born strong to
help those who may be less fortunate.
>> Tano also uses Rangoku's flame guard on
his new sword, keeping his spirit alive.
During the fight, Tano has to reach the
transparent world. To gain access, Tano
remembered his father's Hinami Kagura
dance. The Kagura was revealed to be the
sun breathing technique in disguise.
>> Not only is it the first one ever to be
created, it's the most powerful one as
well.
>> It was demonstrated by Tonerro's father
to be like any other breathing
technique, having to do it thousands of
times to get the movement down before
doing it with ease forever. Later, we
see Aaza's backstory. A's past is really
notable because it shows just how much
his perceptions were twisted after
becoming a demon. Like many pairings in
Demon Slayer, Ring Goku and Akaza can be
considered as foils. One is honorable
and believes the strong should protect
the weak, while the other believes the
weak should suffer for their
inferiority. But by looking at his
backstory, you can see how Akaza was
once similar to Ren Goku. His incredible
resolve to protect the ones he loves,
even if it means getting hurt, parallels
both Tano and the former flame Hashira's
motives. His obsession with growing
stronger stemmed from not being able to
protect his loved ones and despising the
humans who disgracefully wronged him.
But even as a demon, he still has
remnants of his past life, whether or
not it was willing. You can see that his
fiance's hair pin influenced the shape
and designs of his compass needle
technique, and the martial arts fighting
style was influenced by his dojo master.
The fight ends when Akaza realizes he
wants an honorable death to hell and
mutilates himself. The rest of the upper
ranks sense his demise. Upper Moon One
teases Aaza's last words to him, which
we saw at the beginning of the
Swordsmith Village arc.
>> I understand. I'm going to kill you if
it's the last thing I do.
>> With the main fight of the movie wrapped
up, we're still left with many battles
and character matchups for the rest of
the trilogy. The next movie will be
focusing on Kau's battle with Doma to
avenge her sisters and all the victims
that he left in his wake. Enoske is
running through the changing halls
similar to how he did at the Susami
mansion.
>> Coming through. Now, we still have yet
to see who Tokito and Guiome will go up
against. Based on Tokito's heritage of
sunbreathing users, a probable matchup
would be against Upper Moon One. Given
that he looks identical to the renowned
swordsman, apart from the six creepy
eyes on his face, it is very likely that
we'll explore more of their backstory
and family connection. We also have yet
to see Obana and Mitsuri's battle. Given
that we know about Obana's feelings for
her,
>> if they get ripped, then I'll give you a
new pair.
We can expect a flashy fight with them
professing their love or you know a
horrible death in a typical Demon Slayer
fashion. The movie ends with the rest of
the Demon Slayer scattered across the
layer trying to stay alive and find
Muzan. All of these plot lines will be
explored next year in the second part of
the Infinity Castle arc. So guys, that's
the ending explained for you. Huge shout
out to Shinity who wrote this video. You
can find her social links below. And of
course, let us know what you think about
this on all of our socials down in the
comments on Twitter, Blue Sky Threads,
or our free to join Discord server. And
if it's your first time here, I am
begging you. I'm be I'm begging you,
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[Music]