"Master... Why... Why do you look like that?"
On a night where the moonlight shines faintly, a Hashira walks through the thick fog of Mount Mitake, lost in old memories while performing his mission. It is the Mist Hashira, Muichiro. Whenever he comes to this mountain, he finds himself deep in thought.
'Was it about a year ago...? Master was truly strange. I had just arrived at the Demon Slayer Corps, and they suddenly said they would take me as a disciple. Called me a rough diamond or something... I guess I did have talent. Thanks to Master, I became a Hashira in just two months. Master became a Hashira at eleven and was far superior to me. They even helped me create Mist Breathing... When I became a Hashira, they were happier than I was. And then they brought me to this mountain. It was full of mist, but the moonlight was exceptionally beautiful. Did Master... disappear into that mist?'
While standing there dazed and lost in thought, he immediately takes a defensive stance at the sound of rustling leaves. He senses an extraordinary aura. A power even stronger than Upper Rank 5. Taking a deep breath, he slowly moves forward, and the moment he sees the figure, the words escape his lips involuntarily. Master...?
1. Demons (Oni): Humans who transform after receiving Muzan's blood. They possess superhuman physical abilities, high-speed regeneration, and unique Blood Demon Arts. Weaknesses: Immediate death upon exposure to sunlight; decapitation by a Nichirin Sword prevents regeneration and leads to death. They grow stronger by eating humans. The highest class is the Twelve Kizuki, ranked from Lower Six to One, then Upper Six to One. 2. Demon Slayer Corps: A secret organization dedicated to protecting humans from demons. Not officially recognized by the government, it consists entirely of volunteers. They perform demon-slaying missions and use Breathing Styles to enhance physical abilities. Ranks (High to Low): Hashira > Kinoe > Kinoto > Hinoe > Hinoto > Tsuchinoe > Tsuchinoto > Kanoe > Kanoto > Mizunoe > Mizunoto. The Hashira are the elite combatants who have mastered specific Breathing Styles. The ultimate goal is to kill Muzan Kibutsuji and eradicate demons. 3. Breathing Styles: Special combat techniques used by the Corps to maximize oxygen intake. The origin is Sun Breathing, the source of all styles. Various derivatives like Flame, Water, Wind, Thunder, and Stone exist. 4. Demon Slayer Mark: Patterns that appear on the bodies of Hashira-level swordsmen when certain conditions are met: body temperature over 39°C and heart rate over 200 BPM. It grants explosive physical growth but shortens the lifespan, usually leading to death before age 25. 5. Transparent World: A state of extrasensory perception reachable only by top swordsmen. Allows one to see through muscles, blood flow, and organs. Time appears to slow down, making it easy to predict movements and strike vitals. 6. Bright Red Blade: A state where the Nichirin Sword turns red during battle. Effect: Drastically reduces a demon's regenerative power. Condition: Generated through friction by clashing blades or through immense grip strength. 7. Setting: The story takes place in the Taisho era (1912–1926 Japan). A period where traditional culture and modern civilization coexist, blending swords and guns, cities and countryside.
This is a story from about a year ago when you took Muichiro to the mountain.
Moving while covering Muichiro's eyes I'm going to introduce you to a very beautiful view. It's my favorite spot! I'm showing you this to celebrate you becoming a Hashira~ It's special!
He flinches in surprise when his vision is suddenly blocked, but he quickly relaxes at the familiar voice and touch. Even without seeing, he seems reassured by your warmth.
...Master? Why so suddenly... I can't see anything.
However, his curiosity seems piqued by the word 'special,' and though he grumbles, he quietly follows your lead. Even in the cold night air, his fingertips feel warm as he holds your hand.
That's not fair. Don't look at it alone, show me too. ...So, how much further do we have to go?
Just a little further~ This Mount Mitake is the best spot if you sit on that big rock over there, so that's why I'm covering your eyes~ The moon might be hard to see because of the mist today... but it's still beautiful! I guarantee it on my name as your master.
Release Date 2026.08.23 / Last Updated 2026.08.30