#A/N: After rewatching Season 1 of Demon Slayer, I couldn't figure out where Kagerou could naturally fit into the beginning of the story. I mean, it's not like Kagerou, a Hashira, one of the strongest, could accompany Tanjiro and the others on every mission, right? I spent quite some time trying to find the right moment for him to enter the story, but I just couldn't figure it out. So, in the end, I decided to introduce Kagerou directly into Episodes 22-23, during Tanjiro's trial at the Hashira meeting. I hope this works out well!
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- Four Years Later
Four years had passed since Kagerou and Kanae faced the Upper Rank Two demon, Doma. Since then, much had happened, both within the Demon Slayer Corps and in Kagerou's personal life.
After surviving an encounter with an Upper Rank demon, Kagerou and Kanae's reputations within the Corps had improved considerably.
Unfortunately, their victory had come at a terrible cost.
Due to the devastating effects of Doma's Blood Demon Art, Kanae's lungs had suffered severe, lasting damage. Although she eventually recovered from her other injuries and could live a relatively normal life, she could no longer continue working as a Demon Slayer.
Even a few minutes of Total Concentration Breathing placed excessive strain on her damaged lungs. If she pushed herself any further, she risked causing even more harm to her body.
With a heavy heart, Kanae was forced to retire from active duty.
Nevertheless, she continued working at the Butterfly Mansion, where she devoted herself to treating injured Demon Slayers and helping them recover.
Unfortunately, her retirement also affected Kagerou's relationship with Shinobu. For several months, Shinobu refused to speak to Kagerou.
Well, Kagerou didn't particularly mind.
In fact, he was perfectly fine with Shinobu not talking to him.
One hundred percent.
Over the following four years, many things happened within the Corps. There were victories and losses, happy moments and painful ones. Life continued, even as the scars left by past battles remained.
However, among all those events, one brought Kagerou and Kanae more happiness than anything else.
Two years after their encounter with Doma, Kagerou finally proposed to Kanae.
And, of course, she accepted.
Their wedding brought Kagaya Ubuyashiki to tears. He was overjoyed to see his friend finally become a married man.
The ceremony was a private affair, attended only by a small group of family members and the Hashira. It wasn't an extravagant celebration, but it was a meaningful and joyful occasion for the newlyweds.
For Kagerou and Kanae, that was more than enough.
Then, one year after their marriage, Kanae gave birth to a healthy baby boy, whom Kagerou named Homura Rengoku.
... A flame burning within purgatory. (The meaning of the name, by the way)
---
- Butterfly Mansion.
After marrying Kanae, Kagerou Rengoku, now twenty-two years old and considered one of the strongest Hashira, perhaps even the strongest among them, found himself facing an unexpected reality.
No matter how powerful, manly, or respected he was, he still had to live in his wife's house.
The Butterfly Mansion itself.
And that very man was currently sleeping alone in his room. Kagerou lazily moved one hand to the other side of the futon, expecting to feel his wife's warmth.
Nothing.
He opened his eyes.
For a moment, he simply stared at the empty space beside him, then he sat up, blinked a few times, and let out a light sigh.
"...Haa~ Here we go again. Another day, another mission. Should I retire too?" He shook his head. "As if Kagaya would allow that"
*Tok~ Tok~ Tok~*
"Kagerou-sama, breakfast is ready," a young girl called from behind the sliding door. "Kanae-sama wants you to be there"
"Hm~ I'll be there in a few minutes, Aoi-chan," Kagerou replied sleepily.
"Also, you were called to attend the Hashira meeting a while ago-"
"I know, Aoi-chan. You can go ahead. I'll join you guys in a minute, alright?"
"...Okay, Kagerou-sama"
After hearing no further response, Kagerou ran his hands over his face and slowly got to his feet.
"...What a day. It's still early in the morning, and we already have a Hashira meeting?" He let out another sigh. "Kagaya really is clever when it comes to choosing the time"
His voice dripped with sarcasm.
After grumbling to himself for a little longer, Kagerou changed into a simple yukata and tied his hair back.
Once he was ready, he slid open the door and stepped into the corridor. He walked leisurely through the Butterfly Mansion, still looking as though half his soul remained in his futon.
Eventually, he arrived at the dining room, and several people were already gathered inside.
First, there were three little girls: Sumi Nakahara, Kiyo Terauchi, and Naho Takada. Like Kanao, they were survivors of demon attacks who had later been adopted by Kanae and Shinobu, becoming part of their family.
Then there was the girl from earlier, Aoi Kanzaki. Like the others, she had suffered from the cruelty of demons. However, unlike them, Aoi had officially become a Demon Slayer after passing the Final Selection. Due to several circumstances, she had chosen to withdraw from frontline duties and dedicate herself to medical care and managing the Butterfly Mansion's daily operations and logistics.
Finally, there were his wife and their one-year-old son, Kanae and Homura.
"...Morning, everyone," Kagerou greeted them before walking over and sitting beside Kanae, who was busy feeding their son. "Where are Kanao-chan and the Witch?"
"Kanao-san is still asleep. She only returned from a mission a little while ago. As for Shinobu-sama, she hasn't come back since last night," Aoi answered, completely ignoring Kagerou's choice of nickname for Shinobu, as though it were perfectly normal.
"Hmm~ I see"
Kagerou nodded before casually starting his breakfast.
"Dear, you have a Hashira meeting to attend, remember?" Kanae reminded him while continuing to feed Homura.
"Haa~ Don't remind me. You've already ruined the taste of my food"
"Quit acting like that. You're a father now, and you're practically the Corps' vice-leader. You need to set a good example for everyone else," Kanae said firmly, giving her husband a stern look.
"What? Is that position official now?"
"No. But even if you deny it, the others will still consider you Oyakata-sama's deputy. So, finish your breakfast and get to that meeting!"
"Yeah~ Yeah~ Whatever," Kagerou muttered. Then, under his breath, he added, "Ever since we got married, you've started acting like an old woman"
"What?"
"N-Nothing"
Kagerou immediately straightened his posture, pretending that he hadn't said anything.
The others could only giggle at the exchange. Even little Homura seemed to find his father's predicament amusing, letting out a delighted chuckle.
Kagerou glanced at his son.
'Traitor. Even you're taking her side?'
Of course, he kept that thought to himself.
And so, another ordinary morning unfolded at the Butterfly Mansion.
After finishing his breakfast, Kagerou changed into more comfortable clothes suitable for the occasion, adjusted his appearance, and finally set off for the Hashira meeting.
Judging by the time he'd wasted grumbling over breakfast, the meeting had probably already begun.
---
- Ubuyashiki Estate
In the backyard of the Ubuyashiki Estate, within the stone garden, a teenage boy lay unconscious on the ground.
That boy was none other than Tanjiro Kamado, who had lost consciousness after the long and exhausting night he had endured.
A Kakushi approached his motionless body and crouched beside him.
"Oi! Wake up! Oi! Kamado Tanjiro! Kamado Tanjiro! Please wake up!" The Kakushi gently shook Tanjiro's shoulder, attempting to rouse him from his slumber. "Come on, wake up! You can't keep sleeping here! Hey!"
After several attempts, Tanjiro finally began to stir. His eyelids fluttered open, and he slowly lifted his head, looking around in confusion.
"Huh...? Where am I...?"
"You're at the Ubuyashiki Estate," the Kakushi replied. "Now, please get up. You're in front of the Hashira, so get up!"
Tanjiro blinked several times, trying to gather his scattered thoughts. As his consciousness gradually returned, memories of the previous night began to resurface.
His eyes widened.
"Nezuko! Where's Nezuko?!" He hurriedly tried to stand, only to realize that his hands were bound. "Wha...?! Why are my hands tied?!"
"Please calm down!" the Kakushi exclaimed. "You'll find out everything soon enough. Show some respect! You're in the presence of the Hashira!"
Tanjiro looked around the garden, his expression growing increasingly uneasy as he noticed several figures standing nearby.
Then, his gaze settled on the people gathered before him.
Each of them possessed an imposing presence unlike that of any ordinary Demon Slayer.
The Hashira.
"Who-Who are these people-"
"Ouch!"
"Still speaking so boldly! How rude!" the Kakushi scolded, pressing Tanjiro's head down toward the ground. "Who do you think is standing before you?! They are the Hashira!"
'Hashira? What is a Hashira...? What exactly happened here?'