Esoteric Flame Breathing [INDEFINITE HIATUS]

1 - First Encounters of the Heart

About four months after Kyojuro agreed to train the boy, Satoru's body showed signs of improvement after doing months of essential exercise. Before the sudden change in his life, the boy only gained a little bit of strength from the times he helped Suda with his deliveries, but it wasn't enough for him to lift a training sword without any problems. To remedy that, Kyojuro gave him a regime that consisted of Satoru doing thirty push-ups, fifteen handstand push-ups, and ten laps around the entire estate.

While being a demon slayer was what Satoru wanted, even though it wouldn't be an easy path, the boy never realized how difficult this was truly going to be. For starters, Kyojuro would be going on missions to slay demons, so, as much as he wants to, he won't be able to have a lot of time to train the boy himself. Satoru would have asked Senjuro for some assistance, but since he's only seven years old, he will have little to offer to teach, let alone train someone. Another possible trainer for Satoru was Kyojuro's father, who the former discovered was the Flame Hashira, Rengoku Shinjuro. Still, the boy wasn't fond of being around the guy for obvious reasons.

When Satoru turned ten years old, Kyojuro thought that the boy's body was still not ready for the breathing technique, but he agreed to teach him on the day that he could do 100 push-ups and handstand push-ups, along with ten laps around the estate, all without losing his breath once. Since the training to acquire Flame Breathing was more challenging compared to the other breathing techniques, he must take special care to ensure that Satoru's body is prepared for the experience.

At first, Kyojuro had his father train him when he was younger, but that came to a halt after Kyojuro's mother passed away and Shinjuro began drinking whilst doing his duties as a Hashira. Even so, Kyojuro managed to teach himself how to learn Flame Breathing.

After Satoru started living at the Rengoku residence for four years, Kyojuro's rank increased from Kanoto to Hinoto, allowing him to earn more money and get much more challenging missions, making Satoru and Senjuro train themselves for days. Satoru and Senjuro grew closer over time to the point where Satoru earned himself a "big brotherly figure" role in Senjuro's eyes as he was about a year older than him.

However, shortly after Satoru started living at the Rengoku residence, he got caught up in Shinjuro's verbally abusive treatment of his sons. But instead of getting discouraged from becoming a demon slayer, he used it as inspiration to train even harder, to prove the drunkard wrong about how it only requires talent to become a demon slayer.

Deciding that this was the day to start Satoru's breathing training, Kyojuro had him and Senjuro on the training grounds.

Kyojuro: "Senjuro, Satoru, do you know why demon slayers use breathing techniques?"

Senjuro: "To fight the demons!"

Kyojuro: "Correct! But do you know how it works?" Both boys tilted their heads in confusion. "We breathe in specific ways to use our breathing techniques! Also, with our lung capacity being expanded by the increase in oxygen, our abilities and skills, along with clotting wounds, will help us continue to fight, despite being injured!"

Satoru: "Wow... That's so cool!" He exclaimed with an awestruck look on his face.

Kyojuro: *chuckles* "Indeed it is!" He replied with a bug-eyed expression before it shifted to a serious one. "To use Total Concentration Breathing, you must relax your upper body while bracing your lower half. Take a breath, Satoru!"

Satoru took a deep breath, only to suddenly get smacked in the stomach, causing him to lose it as he yelped in surprise.

Satoru: "What was that for?" He asked with a hint of a whine in his voice.