After the events at Sanemi's training ground, Goku decided to change air. Alongside with Zenitsu, the boy was walking on a mountain. "Honestly, I don't know how the hell you're able to get along with that guy!" exclaimed Zenitsu. "Because he respects me and sees me as a strong opponent, that's all," said Goku. Suddenly, the Sun Hashira noticed something. "What's going on, Goku?" asked Zenitsu. "I hear something..." said Goku. Suddenly, as he made a step forward, he noticed a big cascade. "Oh, I guess we found the training ground..." muttered Goku. Under the cascade, there was Inosuke, who was already training. "So you eventually managed to arrive here," said a voice. Goku turned and saw Gyomei Himejima, the Stone Hashira and the strongest among them. "Welcome to my training ground."
"Most important, of all is your body's core," explained the Stone Hashira, once Goku and Zenitsu sat down in front of him. "If you stabilize yourself with a robust lower body, it will lead to accurate attacks and unwavering defense," continued Gyomei. "You'll start off by cold plunging in the waterfall..." he then said. "I'm going to die!" exclaimed Goku. "And that's not all, Tsugikuni. After that, you'll lift up those three logs over there," said Gyomei. "And then, any other things?" asked Goku. "Yes. Eventually, you'll push that boulder, trasporting it one cho away," said Gyomei. "Exactly, how much distance is one cho?" asked Zenitsu. "3,58 feet, Zenitsu-kun," replied Goku. "Fine, fine, let's get started with this waterfall..." muttered the Sun Hashira. But then, he saw Zenitsu had fainted. "Always fainting, Zenitsu-kun..." muttered Goku. "Put him in the river," said Gyomei. Goku did so, and Zenitsu woke up rapidaly. "It's freezing!" he yelled, jumping outside the water. "Sorry, but you weren't waking up, so this was the only option," said Goku. Suddenly, the two boys heard Murata's voice. "Hey, long time no see. Cling to this boulder, it's very warm..." he said, trembling for coldness. In a blink of an eye, Zenitsu sprinted towards tje boulder and clinged it. (It's so warm! I feel like I'm being held in my mother's arms!) he thought.
Goku, on the other hand, entered inside the river. (Zenitsu-kun is right... This water is beyond freezing... But I have to resist...) he thought, while walking forward inside the river. (I already don't feel my lower body anymore...) he thought. But then, Goku turned, and saw Inosuke under the cascade. "Comin' through, comin' through, comin' through!" he repeated. (Inosuke-kun is giving it his all... I should too!) thought Goku, starting to walk up towards the cascade. But then, Goku stopped hearing Inosuke's voice. (Oh crap, he's fainted!) he realized. Quickly, he took Inosuke and pulled him outside the river. "Hey, wake up, Inosuke-kun!" he exclaimed. "Did you call me, boss?" muttered Inosuke, slowly opening his eyes. "Yes, I did..." muttered Goku. Eventually, Goku returned in front of the cascade. (I have to do it...) he thought. And so, Goku got under the waterfall. Beside him, there was Murata. "Whatever you do, don't stop chanting the nembutsu!" he said. "Nembutsu? but I'm not buddhist!" said Goku. "Really? You're not buddhist?" repeated Murata. "No, baka, I'm muslim! Everyone knows it!" answered Goku. "Then how do you focus?" asked Murata. "I have a strong mind..." said Goku.
Finally, Goku got outside the river, panting heavily. (This type of training surely is harsh... Who knew water cascading down from so high felt this heavy...?) he thought, panting. Later on, Goku was sitting around a bonfire bare-chested, eating skewers. Beside him, there was Inosuke, who was eating like a real boar. "So, you became a Hashira without telling me nothing, huh?" he said. "Yeah, sorry, Inosuke-kun..." muttered Goku. "No problem, boss! I'm proud of you!" exclaimed Inosuke. "Hey, Inosuke-kun... Do you think Tanjiro-kun would be proud of me if he were still alive...?" asked the one-eyed boy. "He surely would, boss..." replied Inosuke. "Do you still miss him?" he then asked. "A lot," replied Goku. "Yeah, me too..." muttered Inosuke, eating another skewer. "Gyomei is really strong, don't you think?" said Goku. "Oh, you mean the blind guy? Yeah, he is, but he gives me chills!" exclaimed Inosuke. "Do you think I'll ever get as strong as him?" asked Goku. "Boss, you won't become as strong as him. You'll become STRONGER than him!" exclaimed Inosuke. "Really? You think so?" repeated Goku. "Yeah, of course I do!" replied Inosuke. "I wonder if Gyomei's mark already showed up... I wouldn't be surprised if so..." muttered Goku to himself. "Fine, now that I'm ful... I'll lift up some logs!" exclaimed Inosuke, getting up and putting his boar mask on. "You're all so positive! This is no place for me!" yelled Zenitsu, who was beside the two boys. "Calm down, Zenitsu-kun... Reach us when you feel ready..." said Goku, getting up. "Let's go lift up some logs."
As Goku got in front of the logs, he took a deep breath. "C'mon, let's do this," he said to himself, grabbing three logs. Then, with a big effort, he lifted the three logs. "Whoo-hoo!" he shouted in awe. "Log lift, completed!" said Gyomei. "Really? Already?" asked Goku, placing the logs on the floor. "Yeah, already. Only the boulder remains," said Gyomei. "Fine, and now, at last... Only the boulder remains..." muttered Goku.
Meanwhile, in the Infinity Castle...
Inside Muzan's residence, a new Upper Moon was playing her biwa. This new Upper Moon's name was Nakime. "I have located sixty percent of those demon slayers, but I'm yet to find the demon girl immune to sunlight," she said. "Nakime... You're grown even more than I imagined, how splendid..." said Muzan. "I am honored to hear that," said Nakime. "What about the hidden sun?" asked Muzan. "I've located him, he's alive and well and he's currently training with the other Hashiras. Furthermore, he became the Sun Hashira and has inherited Kamado's earrings after his passing," explained Nakime. "Well, it doesn't surprise me. Technically, those hanafuda earrings belongs to him..." muttered Muzan. "Very well. Both Nezuko and Ubuyashiki... It won't be long until I find them," he continued. "As for the hidden sun, it's only a matter of time before he dies by my hands... I hope he's training well, because very soon, he'll reach his beloved Kamado in the afterlife."
Chapter 48 - End.