Many months later, Hisashi was standing in their backyard with his father.
"You said you want to learn Ki?" Itsuki was surprised by the sudden request from his child.
"Yes. I was heard before when we were at the hospital… Mizuya-dono said something about me using Ki involuntarily. After practicing my sorcery and getting a hang of it, I thought about Ki and heard about it from Ryuya. He said that it is a very useful ability and great power to master."
Over his physical training break, Hisashi has been mastering his newfound sorcery powers and has completed many exercises that would help him control them. He copied different sorcery types from other people and he found out more about his sorcery type. Because of that, he discovered that he can do more than just copy others.
His sorcery allows him to understand other sorcery types and be able to use them for himself. However though, for now, he is only able to copy sorcery spells, exert certain control over others' sorcery, and use a unique type that he can consider his own. He calls it…
'The Neutral Mana'.
After seeing the similarities of sorcery and magic in his drawn story, he decided to be even more unique and call it mana instead of Yoryoku even if the two things are the same.
"I can teach you, however, I can only help you with the basic Ki utilization," Itsuki said to him.
"It's okay, I'm not in a hurry. I just finished mastering Masaru-san's sword style." Hisashi delightfully answered.
"Well then, here's a blindfold I'm going to direct you through it. Also, I'll test your new style then." Itsuki said as he handed him a cloth from his dark sorcery spell.
-In another part of the island (town)-
Ryuya and Sukehiro are currently fishing after class. A fish start to take Sukehiro's bait as he pulls it and a black big salmon-like fish was caught.
"What have been you up to nowadays?" Sukehiro asks. Ryuya, who still hasn't caught anything, just shrugs.
"Nothin', I went to sum towns couple weeks ago. I thought I 'bout foundin' people like you." Ryuya said.
"What do you mean people like me?" the other asks.
"People that can become part of the Seven Ryuzen." Hearing this, Sukehiro looks at him with dead eyes.
"I don't think I can help you with that though. But, I can suggest Hisashi. He'd be stronger than me in the future."
"Don'tcha act like you aren't strong. I'm sure ya can already pass the exams for a normal Ryuzen's troops."
"Nah. I'd defeat you though." "Pfft!" The two laugh at each other.
"Ichika-chan! Who'd ya think would win if the two of us fought?" Ryuya asks as he looks back at a tree.
There, a blushing Ichika peeks out. The two friends knew what she had been doing ever since they left to fish. However, Sukehiro didn't want to embarrass her sister. On contrary, Ryuya is very comfortable with her presence so he decided to ask her.
"Uhm…" She looks at his brother first before saying her answer.
"I think Hisashi-nii would win," Ichika said in her honest answer. Although the answer doesn't have anything to do with the question.
"…" The two just look at her before shrugging their shoulders at the same time.
"What about the two of us though?" Asks Ryuya again.
"Well, brother awakened his sorcery a few months ago so I think he would. But… you are also strong, Ryuya-dono." She said embarrassingly.
"HAHAHAHAHA! I know that! Ya don't have to feel bad. Why'd ya think I got your brother as a frien-"
Ryuya stopped his words for a moment. "-d?" However, his pause became natural as if he never stopped at all. He just looks at Sukehiro who was looking at him before laughing at himself.
Just like him, Sukehiro also knows what was happening as they communicated through their eyes.
'Someone's watching us.' As a next shogun candidate, Ryuya was taught Ki at an early age. Especially when he was deemed to have limited yoryoku by his father's officers, he was plunged into stricter training.
At the same time, Sukehiro who was thought by their father was able to sense the same, albeit a bit later than Ryuya. Only Ichika was oblivious to what was happening.
The two friends acted normal to not alert the person watching them and prevent the worst-case scenario.
Thirty minutes later, the three of them left their fishing spot. At the same time, the observer's presence immediately disappears. The two didn't immediately run back to the town but continued as if nothing happened.
After going back to the town, Ryuya says goodbye to the two siblings as he wants to report this as soon as possible.
"Keep safe man. Don't let the bugs bite cha." Ryuya said as Sukehiro sighed in embarrassment.
"That was bad, dude. Anyways, see you later." As they said their goodbyes, Ryuya run in the direction of the nearest samurai office.
…
As Sukehiro and Ichika enter their house, they saw bruised Hisashi reading a book. When Hisashi saw the two, he stops and takes the wooden sword by his side. He jumps and attacks Sukehiro with a downward slash.
"Brother! Teach me your sword style!" *Woosh* Said Hisashi as his sword's swing sounded through the air. Sukehiro reacted quickly and he unsheathes the sword on his waist to block. "I know you don't use fathers!"
Sukehiro counters by pushing his brother with his sword and a counter-swing. He, of course, flipped it first.
"Your smart-ass wants to fight me, huh? Then come and get it!" Sukehiro yelled as he sends his attack on his brother.
They continued their battle before a voice came out from the second floor of their house. It was their mother doing some house chores.
"If a single piece of furniture or utensil is destroyed there, I will destroy you both at the same time." The yelling made the two kids stop before deciding to do it in their backyard.
Before Sukehiro can step one foot into the backyard, a hand pulls on his shirt.
"Brother… Can I join you? I also want to earn how to use a katana…" Ichika asks. He first looks at his younger brother as the latter nods before agreeing.
"Okay. But you'll start with a small one, okay?" "Yes! Brother! Thank you!" She said as she runs towards the backyard.
"HEY! Thank me too! I also agreed!" Hisashi yells at her but she didn't respond.
Update: Ryuya has limited amount of Yoryoku. It was actually stated to be vast on the manga by Yami's father but he also said that Yami got more. However, based on some instances where Yami drained his magic, I think it is quite less compared to Clover Kingdom mages. They just incorporate it with Ki making the consumption less and more efficient. That's why we saw their spells more on transfomation type than conjuration of spells. This is not confirmed though, just a headcannon.