The next few days passed relatively peacefully. Erika continued her training with Mitsuri as usual, while Akira played...no, trained, with Tanjiro and Inosuke, as usual.
A few days later, Zenitsu finally joined in on the rehabilitation sessions, but, like the others, he was also no match for Pan-chan's overwhelming fluffiness.
By the way, Akira had made two versions of Pan-chan, one for sparring and one for a certain someone's personal use.
Otherwise, that certain someone might have certainly killed him.
Time passed quietly after that. From training and observation, Akira managed to learn the principles behind Thunder, Beast, and Flower Breathing, not every form, but enough to understand their core mechanisms.
The only one remaining was Sun Breathing, but Tanjiro had already promised to show it to him.
However, during those sparring sessions, Akira realized something about his own fighting style.
Later that evening, he sat down with Erika and Selena in their usual telepathic call.
"You know," Akira began, "just saying… I don't think Bartitsu is all that effective against demons."
Selena replied dryly, "Of course it's not. Bartitsu is meant for weak people defending themselves from bullies and ruffians. It relies on leverage and technique, and sometimes even offhanded tricks, not strength. Against demons, it's useless."
"Yeah," Akira agreed, crossing his arms. "That's why I want to learn a new hand-to-hand fighting style."
Erika nodded thoughtfully. "Not a bad idea. But what kind are you thinking of learning?"
"That's the thing," Akira said. "I don't know much about martial arts, so I was hoping you two could help me pick one."
Selena smirked. "Oh, this could be fun. But what kind are we talking about here?"
Akira grinned. "Something cool."
There was silence. The kind of silence that carried disbelief.
"…Didn't you just say you wanted something effective?" Erika asked, slowly.
"Yeah, I said that," Akira admitted.
"But you also said cool," Erika asked.
"Exactly," Akira said confidently. "I want something cool and effective. But coolness is important! What's life without being cool?"
Erika sighed, rubbing her temples. "Yeah, I forgot talking common sense to you never works. Fine, I'll help you pick one."
"Good!" Akira leaned forward. "So what's the coolest martial art that's also effective?"
Erika thought for a moment. "How about Judo? I could even help you train in it."
Akira immediately shook his head. "Nah, too boring."
Selena chimed in, "Then what about Kung Fu?"
Akira tilted his head. "No… I don't know, it's just not stylish enough."
Erika frowned. "Okay… Muay Thai, then?"
"Not bad, I guess," Akira said thoughtfully, "but let's keep looking."
Selena giggled. "If you want style, then how about Capoeira? It's practically a dance, and you could even play music while fighting."
Akira grinned slightly. "Tempting, but not my style."
Erika tapped her chin. "What about Taekwondo?"
"Hmm… not a bad idea, actually," Akira admitted. "But something's still missing."
Selena sighed dramatically. "Alright, brother. You probably had something specific in mind when you brought this up, didn't you? What is it?"
Akira said with an excited smile. "Actually, it's nothing much. But you see… when I first watched anime, I wasn't that interested in martial arts or hand-to-hand combat. I mean, why bother punching someone when you can just nuke them from orbit, right?"
Erika stared blankly at him. "…Only you would say something like that."
"But," Akira continued, "then I saw that one fight. And it changed everything. It was one of the coolest fights I'd ever seen, and I've never forgotten it since. I want to learn that martial art."
Selena and Erika immediately knew what he meant. They didn't even need to ask, as he'd rewatched that battle way too many times.
Selena sighed. "You're talking about Rock Lee vs. Gaara, aren't you?"
Akira nodded proudly. "Yes. I want to learn Strong Fist."
Erika stared at him, deadpan. "Are you seriously saying you want to learn a fictional anime martial art?"
Akira crossed his arms proudly. "Oh, come on. We're literally living in an anime world! That means the world it came from might exist too, right? So that martial art should exist as well!"
Selena sighed. "You do have a point, but… how exactly are you planning to learn it?"
Akira grinned. "Easy. I can copy movements I see perfectly. So I could just replicate it myself."
"Brother," Selena said flatly, "even Sasuke had to train insanely hard for a month to use Strong Fist, even though he copied it with his Sharingan. And even then, he got exhausted after a few moves. You're talking about copying it from memory. How are you going to train it?"
Akira answered with pure confidence, "With hard work and perseverance!"
Selena deadpanned. "Yeah, two things you completely lack."
"Really?" Erika asked, tilting her head, though she knew Akira well enough to find that hard to believe.
"That's not true!" Akira protested. "I am a hardworking person!"
Selena didn't miss a beat. "Then why didn't you try to learn it all these years?"
Akira looked away. "I was just… not that interested."
Selena smirked. "You didn't learn it because you knew how much effort it would take. You got lazy, postponed it, and now that you're bringing it up, you clearly thought of a shortcut, didn't you?"
Akira hesitated. "…Maybe."
Selena's voice turned curious. "Alright, what is it?"
Akira smiled slightly. "Well, training is a form of growth, right? So I thought… what if I used Eclipse to learn faster?"
Erika frowned slightly. "Wait, didn't we agree you wouldn't use Rewrite unless it was absolutely necessary?"
"I'm not using Rewrite," Akira said quickly. "I made a new Noble Art. It's called Exp Overclock. It basically acts as an EXP boost, accelerating growth. I'm going to use that."
"EXP boost?" Erika asked.
Selena blinked. "You made an EXP boost… out of evolution?"
"Yep!" Akira said, his tone proud. "Evolution is just growth, right? So I thought if my Device can make something evolve faster, then I can use that principle to accelerate my growth. So I made a new Noble Art called EXP Overclock. It basically boosts learning speed. With it, I can learn anything faster; no need to train as hard as everyone else. Pretty awesome, huh?"
Erika crossed her arms. "…That actually sounds useful."
Selena nodded approvingly. "It's a solid idea. We could speed up progress on a lot of fronts. But, brother, can you use it like an EXP share?"
Akira thought for a moment. "In theory, yes. But I don't know how to apply it to someone else yet. For Eclipse to work on another person, I need physical contact. That's fine for Rewrite, but EXP Overclock requires a constant connection, so it's not possible to use it on others. At least, not yet."
"I see," Erika said softly. "Guess I'll just have to do things the old-fashioned way."
"Huh? No," Akira said suddenly, "I can use it on you."
Erika blinked. "What? How?"
"Well…" Akira looked slightly hesitant, scratching his cheek. "Remember how you've been drinking my blood a lot lately?"
Erika said. "Yeah. What about it?"
"Whenever you do, I feel something in my heart," Akira said seriously.
"…Really, what do you mean?" Erika blushed faintly, her voice a mix of curiosity and embarrassment.
"The Sacred Gear, Lunar Vows, activating," Akira replied.
Erika gave a deadpan look. "Oh. I see."
"Yeah," Akira continued, "and I still don't fully understand how it works, but… with it, I can feel my blood inside you."
"Yeah," Akira continued, "and I can actually feel myself inside you."
Erika froze. "Wait, WHAT!?"
"Not just that, I am basically touching you all the time," Akira said in a most serious expression.
"W-W-What nonsense are you talking about?" Erika asked in complete confusion and embarrassment.
"Wow, brother, phrasing", Selena deadpanned.
"Basically, because of you drinking my blood and the lunar vow sacred gear in me, and it's connection between us, I can feel my blood inside you, and it's basically like I am touching you all the time," Akira explained calmly.
"Oh…I see", Erika calmed down.
"Not just that," Akira went on calmly, "with that connection between us now. It means I can channel Exp Overclock through that link. The effect and duration still need testing, but best case, I can use it on you the same day you drink my blood."
Erika's eyes widened slightly. "So… that means I can learn faster too?"
Akira nodded. "Exactly."
Selena's voice came through telepathically, warm and amused. "That's actually a good development. Erika-chan, try testing it during training today and see how it feels, okay?"
"Got it," Erika replied, a small smile forming. "Oh, and Akira, what about you? Same old training today, or are you starting to learn Strong Fist?"
Akira smirked. "No, not today. Tanjiro said he's finally going to show me the Hinokami Kagura. I need to focus."
Selena teased, "Oh? Is it finally time?"
Akira crossed his arms and said in a dramatic, villainous tone, "Yes. The day I've been waiting for has finally arrived."
Erika sighed. "Sometimes, I'm not sure how old either of you actually are."
And so, Erika went off to train with Mitsuri, while Akira made his way to meet Tanjiro.
When he arrived at the courtyard, he noticed Tanjiro was alone. Neither Zenitsu nor Inosuke were anywhere in sight.
"Where are the others?" Akira asked, glancing around.
Tanjiro said in an awkward expression. "Ah, they're still resting in their rooms. I will definitely bring them tomorrow."
Akira blinked once, then smirked. Right… just like in the anime.
"Don't worry about it," he said lightly. "So, are you finally ready to show me your Hinokami Kagura?"
Tanjiro nodded firmly, his expression calm yet burning with quiet determination. "Yes. Please watch closely, Akira-san."
Then, Tanjiro began.
Akira folded his arms, and his Mystic Eyes of Truth glowed faintly.
Tanjiro's movements flowed like fire dancing through the wind, rhythmic, graceful, and powerful. Each step carried a distinct tempo, each breath synchronized perfectly with the swing of his blade. The faint aura of heat surrounding him shimmered like sunlight breaking through the mist.
Akira watched through his Mystic Eyes, dissected every detail, each breath, each pulse of energy, every fluctuation in circulation.
It was powerful. Far more than any other Breathing Style he had seen. But also… flawed.
He could see the inefficiencies, the way energy spiraled unevenly through Tanjiro's body, how strain built up in his chest and arms. So much power, yet so much waste.
"Perhaps because it wasn't the true Sun Breathing created by Yoriichi", Akira thought. "But even so, it surpasses all others".
The energy circulation was inefficient, but the technique itself is magnificent. However, it placed an incredible strain on the body. Overuse could cause muscle collapse, even organ failure.
When Tanjiro finished, panting slightly then he turned to Akira and asked earnestly. "So… what do you think, Akira-san?"
Akira smiled faintly. "It's incredible. This Breathing Style surpasses every other I've seen—even the Hashira's."
Tanjiro's eyes widened. "Really?"
"Yes," Akira said. "But it's also dangerous. Mastering it won't be easy. Still… if you can fully control it, you'll become stronger than anyone else."
Tanjiro looked amazed but also hopeful. "Do you think it's connected to Nezuko's condition?"
Akira shook his head slightly. "Not directly. It might have played a role, but those blue cells aren't from this technique. They're something else entirely."
"I see…" Tanjiro murmured.
"Don't worry," Akira said reassuringly. "I'll find out what's going on. Your sister will become human again."
Tanjiro's eyes softened with gratitude. "Thank you, Akira-san… for everything."
He bowed deeply, then left the courtyard, his steps lighter than before.
Once he was gone, Selena's familiar voice echoed telepathically in Akira's mind.
"So, you finally have all the Breathing Styles now. Are you going to create your own soon?"
Akira looked up at the sky, a small smile crossing his lips. "Yeah… It's time."
The morning wind stirred around him, rustling the wisteria leaves outside the Butterfly Mansion.
For Akira, the moment had come to forge something entirely his own.
He gazed up at the clear blue sky, eyes reflecting quiet determination.
"I'll create a Breathing Technique," he murmured, "that will help me reach the stars."
There was a pause.
Then Selena's voice echoed telepathically, flat but teasing. "Wow, brother… even for you, that was kinda cringe."
Akira groaned. "Oh, shut up."