Chapter 51: The Rengoku Family

Anyone who has seen Ubuyashiki Yoriichi knows that his current appearance has nothing to do with the word "handsome." The purplish patches on his forehead are terrifying to behold.

You're telling me this spread over the course of a year? At this rate, won't the leader be completely blind in another year? Wait... I remember that before the decisive battle at the Infinity Castle, the leader was already blind and his body was failing. Isn't the leader's current condition just as dire?

"Did something happen last year?"

"The leader said he seemed to have seen something, and this is the price. The exact reason is unknown... The Ubuyashiki family has intermarried with priestly families for generations, so it's normal for them to possess mysterious abilities," Rengoku Shinjuro said. "From what the Rengoku family has observed over the generations, the leader's family has extraordinary observational abilities and has not suffered any calamities for nearly a thousand years. The most dangerous time was during the Warring States period hundreds of years ago, when a swordsman who practiced Breathing Techniques became a demon."

After a pause, Rengoku Shinjuro continued, "So, how was it? Junior, have you experienced the process of being escorted to the leader's house by the 'Kakushi'?"

"I have, and honestly, it was terrible. The whole process was just talking to myself."

"Haha, it won't be like that in the future. Next time, it'll be easier when you go to a Pillar meeting!"

"When I left, it was under the guidance of the 'Kakushi.' Mr. Rengoku, I came to ask you something."

Rengoku Shinjuro nodded, "Your purpose was explained in the leader's letter. I'm about to head home, so why don't you come with me to look through some books? I don't remember this kind of thing myself!"

He wasn't ashamed of his shortcomings. If he didn't know, he didn't know. His answer was straightforward.

Rengoku Shinjuro was a passionate man, true to his title as the "Flame Pillar." After resting for a night, he immediately set off for his home, traveling on foot.

The limitations of the era meant that trains only reached certain places, roads hadn't been built everywhere, and horses were a scarce resource. Feet were still the most common means of transportation.

The Rengoku family's pace wasn't slow. Although there might be a gap between Pillars, Li Mo's upgrades and enhancements allowed him to keep up without issue.

"Junior, you're quite strong! Haha, being able to keep up with my pace, I'm really happy to see such an outstanding junior," Rengoku Shinjuro said with a smile.

"Isn't your speed a bit fast, senior?"

"I can't wait to see my wife!"

They arrived at the Rengoku household. Following the path, they stopped in front of a courtyard. Rengoku Shinjuro pushed open the gate and saw a child standing in the yard. He went forward and hugged the child, lifting him up happily, "Ah, Kyojuro, you've gotten heavier!"

"Father, welcome back," the young boy smiled, showing the same expression as his father. "Is this a guest? Hello, my name is Rengoku Kyojuro, I'm Father's son! Nice to meet you!"

Rengoku Kyojuro, twelve years old, was Rengoku Shinjuro's eldest son.

For a time traveler, the name Rengoku Kyojuro was thunderously familiar. His death would mark the beginning of the final battle, the culmination of the thousand-year feud between the Demon Slayer Corps and Muzan Kibutsuji.

But now...

"Hello, I'm Li Mo," Li Mo shook the small hand extended by Rengoku Kyojuro.

Apart from Rengoku Shinjuro, the head of the family, and his eldest son Rengoku Kyojuro, the Rengoku household also included the mother, Rengoku Ruka, and the second son, Rengoku Senjuro. Getting along with this family was easy. The Rengoku family was warm and cheerful, and their behavior never made anyone feel awkward. The only serious one was Rengoku Ruka, the mother. Upon learning of Li Mo's purpose, she went to the study to look for relevant books, and Rengoku Shinjuro followed.

Li Mo and the two children stayed in the courtyard. Senjuro was only a year or two old and had just learned to walk. Previously, Rengoku Ruka had been taking care of the child. But since she was helping him, it was only natural for Li Mo to help look after the child.

—Or so he thought.

Rengoku Kyojuro crouched down, encouraging Senjuro to walk. Even if his younger brother fell, he wouldn't immediately help him up, instead saying seriously, "Senjuro, you can do it. Come on, stand up."

Li Mo, having spent some time with the Kamado family, suggested, "How about supporting him while he walks? It would be easier."

Rengoku Kyojuro refused the suggestion. Senjuro had been able to walk this distance a few days ago, so there was no reason he couldn't do it now. The Rengoku children didn't need help with things within their capabilities.

Wasn't it awkward just watching? Like someone else was working while he was slacking off, not helping. Li Mo's sense of shame hadn't completely disappeared, but he soon accepted it. He crouched down next to Rengoku Kyojuro and encouraged Senjuro to slowly walk over.

Dealing with children was the easiest. Their emotions were all on their faces. After playing for a while, Senjuro felt tired and sat down, dozing off.

Rengoku Kyojuro looked at his sleeping brother and then asked Li Mo, "Mr. Li Mo, is your Breathing Technique 'Sun Breathing'? Ah, it's a Breathing Technique I've never heard of! Did you create it yourself?"

It seemed Rengoku Kyojuro didn't know that "Sun Breathing" was the origin of all Breathing Techniques. In the original timeline, Rengoku Kyojuro didn't know the story of "Dance of the Fire God" and the Hanafuda earrings.

Li Mo tactfully told Kyojuro that it wasn't a technique he created but one he inherited from someone else.

"I see! I heard that Mr. Li Mo mastered 'Total Concentration: Constant' before participating in the Final Selection? That's really impressive! Father only mastered that skill several years after becoming a Demon Slayer. Do you have any tips?"

Breathing Techniques speed up blood circulation, increasing the body's energy and enhancing physical abilities. Ordinary swordsmen can master Breathing Techniques but can't use them constantly. The lungs and heart might not withstand the pressure. "Total Concentration: Constant," which maintains the Breathing Technique continuously, challenges both the body's limits and one's willpower.

Li Mo said, "The trick is to blow up gourds. Blowing up specially made gourds can train you. Once you blow up one gourd, you move on to a bigger one."

The gourd-blowing training method was something he borrowed from the original story, and it worked quite well. His quick mastery of "Total Concentration: Constant" was partly due to this training.

Later, Rengoku Kyojuro asked Li Mo to spar with him. Li Mo didn't refuse and instead fed Kyojuro moves. He knew nothing about "Flame Breathing," but having sparred with Sabito and Giyu Tomioka before, and given the significant gap in their abilities, Li Mo handled it with ease.

When Rengoku Ruka and Rengoku Shinjuro reappeared, they had found information on "Sun Breathing" in ancient texts. The summary was that "Sun Breathing" was the origin of all Breathing Techniques, and that the unnamed swordsman had been expelled from the Demon Slayer Corps. The Rengoku family's ancestors had maintained contact with him and helped him replace his Nichirin Blade, among other details.

Apart from some specifics, the Rengoku family's records matched what Li Mo already knew.

"If Ruka weren't here, I wouldn't have been able to find such detailed information. Haha! I'm so lucky to have Ruka as my wife!" That day, Rengoku Shinjuro said this.

The relevant information was found in multiple ancient texts, many of which were fragmented. It was only because Rengoku Ruka had organized the Rengoku family's ancient texts earlier that they were able to find it so easily. Rengoku Shinjuro couldn't have done it.

He didn't even know how many ancient texts his family had.

Li Mo stayed at the Rengoku household for two days, during which he trained with Rengoku Kyojuro and fed him moves. Then, on that day, Li Mo received a new mission.