Over the past year, Marume Kurando had been quietly watching Itsuki. He couldn't help but notice the kid's crazy appetite—and the way his body just kept getting stronger. That alone was weird enough, but when Itsuki started taking swordsmanship seriously, something clicked for Kurando. The kid reminded him of himself when he was younger.... Well except that huge ass appetite.
After their last talk, Kurando started to genuinely pay attention to him.
It'd be a waste if someone like Itsuki who is smart and strong, had no shady background and actually gave a damn about training, just got overlooked.
But even though Kurando wanted to help, he chose not to teach the kid personally after starting to teach him for a month. It wasn't because he didn't want to. He just knew he wouldn't be able to keep up with someone like Itsuki for long. The boy was growing too fast. What he needed was a better teacher. A real one.
That's when Kurando thought of someone—Rengoku Shinjuro.
Yeah, that Shinjuro. The current Flame Pillar of the Demon Slayer Corps. Probably for not long though, He wasn't doing much these days, either. Some personal stuff happened, so he stepped away from the frontlines. But he was still the best shot Itsuki had.
Kurando knew about him because of his past.
He came from an old-school swordsmanship family. His whole life had been about martial arts. But unlike his relatives, he wasn't all about family pride. He knew real strength didn't come from tradition—it came from the Breathing Techniques.
He still remembered it clearly. Back when he was young, he saw a Demon Slayer take down a demon. The way the thing healed instantly, and the breathing style that cut it down... it stuck with him. It looked like something out of a dream.
So, he chased that power. Somehow, he made it to the Demon Slayer Corps and even got a shot at learning Flame Breathing.
Kurando had the talent, no question. He picked up the techniques quickly. But the thing is it was his body that didn't keep up. His Flame Breathing didn't last long enough, and in the end, he couldn't pass the final test.
He never forgot how close he came. He didn't quit like the others. Instead, he went off on his own, trained for a decade, and built his own version of what he learned. That's how his Flame Blade Swordsmanship was born.
To pass it on, he used his family's connections to start the Ren Martial Hall in Yoshiwara.
The place got popular fast. And eventually, the Demon Slayer Corps noticed. They approached him and said if he found any talented kids, he should send them their way.
Now, with Itsuki, Kurando finally had someone worth recommending.
So that night, he sat down and wrote a letter to Shinjuro.
Itsuki had no idea any of this was happening. While he was still worrying about how to find a Breathing Technique master, the path was already being laid out for him.
Five days later, the letter reached the Rengoku household.
"Dad, you've got a letter!"
Senjuro, the younger son, ran up to the door and knocked. No response.
He sighed. His dad was probably passed out drunk again. So, he just left the letter by the door and went back to the courtyard to train on his own.
Since their mom passed away, things hadn't been the same. Their dad barely spoke anymore. He drank all day and had completely stopped teaching them. And now that Kyojuro had joined the Corps, Senjuro was alone with just his wooden sword.
The house fell quiet again.
Around noon, Shinjuro woke up. The sunlight through the window was bright and annoying. He reached for his empty sake bottle, sighed, and got up to head out for more.
As he opened the door, his foot nearly landed on the letter.
"Tch. Another one of those damn letters from HQ? Telling me to get it together or whatever..."
He was about to ignore it, but something caught his eye—a seal. One he hadn't seen in a long time.
The Ren Martial Hall.
His eyes sharpened. He bent down, picked it up, and opened it.
By the time he finished reading, his face had changed.
A kid who mastered the Flame Blade style in a few months?
A 15-year-old with insane physical ability and a strong drive to get better?
Even if 15 was a little late, with that kind of body, he could still handle the load Breathing Techniques required.
This kid had the kind of talent that only came around once in a generation.
Shinjuro's hands trembled slightly. For a second, something in his heart stirred.
Then he sighed.
So what if that kid became the next Flame Pillar? That was just another repeat of what happened to him. Another tragedy waiting to happen. He couldn't even protect his own wife. His own son is trying to become the Flame pillar.
The light in his eyes dimmed again. He dropped the letter and headed outside. There were still a few bottles in the shed.
The sunlight stung his eyes. He lifted a hand to block it.
Too damn bright.
He turned to go back inside, but then—
Thwack!Thwack!
The sound of a wooden sword cutting through air reached his ears.
He looked towards the sound.
Senjuro was in the courtyard, swinging his sword over and over again. His form was awkward. His shoulders were tense. His movements were stiff.
Shinjuro almost yelled at him. But something stopped him.
He just stood there, watching.
That kid. He wasn't strong. He wasn't even talented.
But he kept going. Alone.
Just like I used to...
Shinjuro didn't know what came over him. His eyes stung for a second. Then he slapped his cheeks hard and squared his shoulders.
"Idiot! That's not how you train Flame Breathing!"
His voice echoed through the courtyard like thunder.
Senjuro froze. He turned slowly. That voice—he hadn't heard it like that in a long time.
"F-Father?"
"You're wasting time swinging like that. You need a real opponent."
Senjuro blinked. Was... was his dad back?
"Yes!"
"We're going to Yoshiwara tomorrow. I found someone worth training. Pack your stuff up and let's go."
And just like that, Shinjuro turned and walked back inside like nothing happened.
Senjuro stood frozen, a spark of hope quietly blooming in his chest.
Maybe things were finally changing.