Chapter Text
Chapter One: The Substitute
-Class 1-A-
Deku was sitting in his seat ready for another day of Hero Training, he was glad that he was staying in the Heights Alliance. It did make the commute to UA easier. Though he had noticed something recently, the empty rooms on the second, third, and fourth floor had been put to use. Meaning that there were new students for Class 1-A, yet there was no one new. Then the door slid open as a young woman in her mid twenties walked in carrying a large treasure chest into the room. She had white hair, yellow eyes, glasses, and fair skin. She set the chest down and began to write on the board:
Urata Hanako, substitute.
Beneath that:
If D-san pays A-san 15,203,079.21 yen to fix his deck and A-san pays B-san 1,520,307.92 yen to fix the deck and B-san pays C-san 152,030.79 yen to fix the deck and C-san pays D-san to fix the deck for 15,203.08 yen. Who is it that loses the most money? Who repairs the deck? Who gets in the most trouble? Who is going to be on the run for a year (the correct answer for this one is A,B, and C)?
And a drawing of a wild eyed man (Sanemi) chasing after a figure with C for a face. A broken deck in the background as another figure (Genta) stared at it.
“Good morning everyone, I’m your Substitute teacher for… an undetermined amount of time.” Hanako said as she stood at the front of the class, a look in her eyes saying she has seen far worse in her teaching career. “Unfortunately, all of your normal teachers have gotten sick with a cold and they don’t know when they’re going to be back. At least a week. I’m Urata Hanako, you could say my Quirk is High Muscle Density. My rules? No starting a government in class and no starting cults.”
“What’s with the problem on the board?” Kirishima asked loudly and Hanako looked at him. Minoru was just wondering what she was talking about by starting governments and cults.
“That is today’s problem, you see I’m offering you a choice, I can easily go with the lesson plan today.” Hanako said as she leaned against the desk and held up one finger before holding up the second one. “Or you can solve the problem. If you get the answers right, I’ll allow one of you to draw a sur-prize from the chest and then we can try out my lesson plan! And don’t worry, I already talked to the principal and got permission for this.”
Deku took note of manuals on her desk, each of them in stacks of six. Each stack contains twenty books each.
Hanako saw the kids kind of glance at each other, some were already taking the challenge. Her sur-prize? Family sized snacks, a huge amount that she managed to fit in there. ‘Mitsuri-senpai’s suggestions are going to shock these kids… not as much as when they finish it… speaking of finishing.’ Hanako’s thoughts went to lunch as she pulled out a nine tiered lunch box and began to eat it while she mentally took attendance. They were all there, she did a headcount, twenty heads meaning twenty students… It was hard with Toru but her uniform was there and moving.
Aoyama Yūga ✓
Ashido Mina ✓
Asui Tsuyu ✓
Īda Ten'ya ✓
Uraraka Ochako ✓
Ojiro Mashirao ✓
Kaminari Denki ✓
Kirishima Eijirō ✓
Kōda Kōji ✓
Satō Rikidō ✓
Shōji Mezō ✓
Jirō Kyōka ✓
Sero Hanta ✓
Tokoyami Fumikage ✓
Todoroki Shōto ✓
Hagakure Tōru ✓
Bakugō Katsuki ✓
Midoriya Izuku ✓
Mineta Minoru ✓
Yaoyorozu Momo ✓
Soon everyone was curious and began to work on the problem. Hanako took this chance to pass out the books. Manuals (History, training, strengths and weaknesses all in one) on Flame, Thunder, Wind, Stone, Water, and Total Concentration Breathing. ‘Mm, they are always relying on their Quirks. Time to show them how the Quirkless fought Oni.’
Hanako’s High Muscle Density wasn’t a Quirk, it was just a random genetic twist that made her like her hero Kanroji Mitsuri. Who had helped her find her path when she had lost it in high school. ‘And was thrown back in time with my gang. This time I’m going to help these punks.’ Hanako nodded her head as she continued to eat. Like Mitsuri she did require large portions so her body could keep up. Then Momo raised her hand rather quickly.
“The one who loses out the most is D-san, no one repairs the deck since it is broken in your drawing, the one in the most trouble is A-san because D-san originally paid A-san. A-san, B-san, and C-san are all on the run for the entire year if they managed to escape.”
“Correct Yao-chan!” Hanako pointed at her with a grin. “Now, then, the real question is did they escape D-san’s wrath? Actually, first get up here and get your prize.”
Hanako kicked a hidden switch and the chest opened up revealing the massive amounts of snacks contained within. After Momo finished grabbing her treat, nothing that Hanako brought was small, Hanako closed the lid. “Alright, now did any of them escape D-san’s wrath?”
“Depends on the Quirk!” Ten'ya called out and Hanako brought her arms up forming an X. “Why not!”
“Because, they didn’t know about D-san coming after them.” Hanako said as she tapped her finger against the drawing. “D-san caught C-san first, then went after A-san, finally catching B-san. He outmaneuvered and used a technique to boost his speed. Mineta-san! Please read to the class from the Total Concentration Breathing Manual! Page one, the description!”
Mineta took a deep breath before reading. “Total Concentration Breathing is a technique developed to maximize physical capabilities by utilizing controlled breathing to enhance oxygen intake, improving muscle efficiency, perception, and stamina beyond normal limits. When mastered, it can be sustained indefinitely, strengthening the body at all times.”
“What the hell, this crap sounds fake.” Bakugō started, Hanako looked at him before saying.
“So you’re too much of a coward to try it out?” Hanako asked and Bakugō’s eye twitched. “A shame, you see the other five manuals. We were going to start with Breathing Forms. Giving you a foundation to start, then moving on to Total Concentration Breathing, then mastering it. If you don’t want to join, that's fine.”
Hanako moved to stand in front of him before setting down a paper with a hard slap and there was a cracking sound. It was the desk as she moved back and Bakugō checked under his paper seeing that she had bent the metal underneath the wood. “But you and I both know you won’t, ya little punk.”
“That goes for the rest of ya!” she said loudly looking around. “Your physical foundation is weak! The moment you lose those powers where will ya be at! HUH? I’m gonna be trainin’ ya, all of ya, to prepare for the worst case scenario! You chose to do the problem, now we’re doing things my way. So choose a Breathing Style that seems interesting, write it down. Total Concentration is not going to be one of them, you will most likely pass out. Flame, Water, Wind, Thunder, or Stone only. Once I gather the papers, I’ll put the groups on the board and we’ll continue from there.”
A few minutes later, once everyone was done, Hanako gathered the papers. She walked up to the board.
Flame:
Bakugō Katsuki
Kirishima Eijirō
Ashido Mina
Īda Ten'ya
Water:
Kōda Kōji
Yaoyorozu Momo
Sero Hanta
Asui Tsuyu
Wind:
Tokoyami Fumikage
Mineta Minoru
Ojiro Mashirao
Todoroki Shōto
Thunder:
Aoyama Yūga
Kaminari Denki
Midoriya Izuku
Jirō Kyōka
Stone:
Satō Rikidō
Uraraka Ochako
Hagakure Tōru
Shōji Mezō
“Right! That’s all done!” Hanako said as she clapped her hands together as both doors to the classroom opened up. Five men walked in. “Let me introduce you to the Breathing Masters: Rengoku Kyōjuro Flame Breathing Hashira and Master, always looking for students who won’t run away!”
“IT IS AN HONOR TO MEET YOU!” Rengoku announced loudly. He had wild blond hair with red tips, his red to gold eyes were wide as he stared at everyone. He stood at 177 cm wearing a black Gakuren uniform with a white haori with the bottom torn to look like flames and the bottom had a red flame pattern on it.
“Water Master: Urokodaki Sakonji!”
“Hmmm.” the man was wearing a tengu mask, but Deku could tell that he was elderly. He stood at 177 cm, with a cloud patterned jinbei kimono. He had white hair.
“Thunder Master: Kuwajima Jigorō!”
“Which ones are the brats I’m supposed to be training?” Kuwajima asked, he was short, about 134 cm, with white hair, bushy eyebrows and mustache, a six pronged horizontal scar running across his left cheek, a peg leg, and a cane. He was also wearing a jinbei kimono, but brown with triangles.
“Wind Breathing Hashira and Master: Shinazugawa Sanemi!”
Standing at 179 cm, with long spiky white hair, large almond eyes that had purple irises, scars, and a look that screamed death. Sanemi was judging them before clicking his tongue. Mineta realized that Sanemi was D-san rather quickly.
“And the Stone Breathing Hashira and Master: Himejima Gyōmei.”
A muscular blind man with a horizontal scar across his forehead standing at 220 cm carrying prayer beads and an olive green happi was draped over his shoulders.
“Please gather around the teacher of your chosen breathing style and no, you’re not allowed to switch.” Hanako said, seeing the look of fear in Mineta’s eyes.
“Remember, these men are not just breathing masters, but expert swordsmen, they will train you the way they learned.” Hanako said as she finished her bentō. “So, in my class, you’re not going to be using your Quirks while you train. Ah! We should go to the training grounds now! Let’s go! Let’s go!”
She had taken them to Ground Omega, with the vast forests. She looked at the Trainers. “Alright guys, don’t hold back on them. Train them like you would your own students, just don’t kill them. Please, we need the money to fix the deck. They also have math lessons, English lessons, Japanese lessons, History lessons and I have to cover all of them while their actual teachers are recovering.”
“No promises, HEY BRATS! Gchk… Tokoyami, Mineta, Ojiro, and Todoroki. You’re the ones who chose Wind Breathing huh?” Sanemi asked with a crazed grin forming across his scared face. “Come with me.”
“Bakugō! Kirishima! Ashido! Īda! Follow!” Rengoku called before leading them in a different direction. The group following him. Aoyama Yūga, Kaminari Denki, Midoriya Izuku, Jirō Kyōka followed Kuwajima. Kōda Kōji, Yaoyorozu Momo, Sero Hanta, Asui Tsuyu followed Urokodaki. Satō Rikidō, Uraraka Ochako, Hagakure Tōru, and Shōji Mezō followed Himejima. Hanako went to keep an eye on things but doing some training herself. “Remember guys! Don’t use your Quirks! And Shinazugawa-san, no knives or nichirin swords. If they use their Quirks… battle it out like you did with Kamado-san.”
-Flame Group- Rengoku Kyōjuro as the Teacher-
He first started them with something easy, well that was what they thought when they heard the word “running”. Running a single lap around the entirety of Grounds Omega, 4 km, with a pack of logs that weighed 20 kg. With Rengoku running behind them. And that if he caught them they would have to start the whole run over. Then after that it was 1,000 bokken swings, followed by push ups, sit ups, squats, planks, holding squats all the while maintaining breath control. Then there was lunchtime. Rengoku made sure they had a big meal. During that time he had vanished allowing them time to rest while he went to a steam room to increase his endurance. He was fully clothed. When he returned it was back to training, more pushups, this time next to a campfire. Footwork training, maintaining breath control, and more jogging until it was time for them to return to the dorms. All the while they heard Mineta’s screams echoing through the grounds. They had completed day one without using their Quirks.
-Wind Group- Shinazugawa Sanemi
He had gone all in before they had a chance to ask any questions.
“If any of you think about using those fancy Quirks of yours I will make sure that you will regret even that.” Sanemi had warned them at the start. His eyes glaring towards Mineta, who he viewed as a coward, and Todoroki, which didn’t make sense to anyone but Sanemi. ‘He reminds me of that bastard Tomioka.’ Sanemi thought before he began the training. “So we’re going to start with something very easy. Dodging.”
Sanemi began to simply throw rocks, using his strength, and they used their Quirks. Sanemi’s eyes and grin widened. “You brats really do love living on the wild side don’t you? What was the one rule I gave?”
“D-don’t use Quirks?” Mineta said and Sanemi looked at home. “Oh… shit.”
“That’s right, don’t use your fancy little quirks and you all couldn’t help yourself.” Sanemi walked over to them. “So, we’re going to have a change of plans.”
He grabbed Mineta by the head as he crouched down. “And all of you are going to learn how to listen.”
His hand gripped the sheath of his katana. “Run.”
“W-What?” Mineta asked as Sanemi released his head.
“I’m giving you three seconds.”
The four boys took off as Sanemi stood to his full height of 179 cm, pressed his feet against the ground and took off after them. Ojiro tried to use his tail to pull himself up into a tree. Sanemi rotated his body to jump up, pulling out a bokken and hit it against the thickest part.
“Roku no kata: Kokufū Enran!” He slashed downwards with a bokken in his hand, creating an arched slash which sliced through the thick branch super close to Ojiro’s body but not close enough to do damage.
“Are you trying to kill us?!”
“If I was you’d already be dead!” Sanemi shouted. “What the hell do you think Wind Breathing is?”
“Soft and gentle?!” Mineta cried.
“It’s speed you shitstain!”
Mineta screamed as the blade got too close to him.
When Deku got back to the dorms with his group: Aoyama Yūga, Kaminari Denki, Jirō Kyōka. They were exhausted. Despite his appearance Kuwajima was rather dedicated to having them all know what Thunder Breathing was about and seeing them train for it. Thunder Breathing was about speed and precision, he trained them to focus on channeling their strength to their legs for the first day. So it was a lot of exercises to do just that. However upon seeing the other groups he wondered what they had to go through. Everyone was on the ground. Mineta was whimpering. Uraraka was talking about strength training. Yaoyorozu mutters something about how Urokodaki did not like the fact that the highest point in Ground Omega didn’t have thin enough air. He had explained and drilled them on how to descend the mountain successfully and repeatedly, how to breathe properly to gain power, the intricacies of the weapon and the forces behind it, sparring with them to improve their endurance and stance using only their bare hands, and getting them used to harsh conditions throughout the day. The door opened as Hanako walked in with the five trainers right behind her carrying food.
“One, good job.” Hanako said as they set the food down on the counter. “You mostly survived their training… somewhat intact. Two, meet the new occupants.”
Silence.
“Yup, these guys are going to keep an eye on all of you, from your diets all the way to your sleeping habits. Don’t worry, I’ve explained to Shinazugawa-san that he is not allowed to ambush you in the dorms and is only allowed to wake you up.” Hanako said as she looked at him. “It’s punishment for choosing violence over brutal punishment.”
“Same thing.”
“You sir need to work on your social graces, you are not in the Taisho Era hunting demons anymore.”
“Yeah, I’m babysitting overpowered brats, there is no difference.”
“They don’t eat people.”
“Ummm, does this mean we will be training outside of school hours?” Deku asked and Hanako looked at him as everyone else gathered around the food. Which was traditional Taisho Era food.
“Yes,” Hanako told him as she tilted her head to the side. “Don’t worry, this would be more like extra credit. Before school it will be training with all five of them while during school it will be with the trainer of your chosen Breath Style. I know it’s hard and that it feels like your legs or arms are going to fall off. But remember this, the Breathing Styles were meant to give those without powers a boost so they can face those who were more powerful than them in every way. A lot didn’t make it, but those that did suffered a lot. It’s why you should understand why they are the way they are. Rengoku is straightforward and honest because that is how he is. He believes that those who are gifted with strength should protect the weak. Like a hero. However I’m also your teacher which is why you’re going to eat, bathe, do your homework, and go to bed. You’re going to need as much sleep as possible and I don’t want you to have Aizawa come back asking for the homework assignments he gave me.”
“We still have to go to school?!” Mineta whined and Sanemi glared at him, causing him to shut up.
“Yes, now eat.” Hanako said, and when Deku had his first bite he felt like it tasted so good. It was well salted, the miso soup wasn’t overwhelming, the fish was delicious. Everything was.
“I don’t get it.” Momo suddenly spoke up, setting her chopsticks down. “This is… nutritious and well-balanced, but it’s nothing extraordinary. Why does it taste so good?”
Urokodaki, who was sipping his tea, his mask only slightly lifted, spoke. “Because your bodies are starving for proper sustenance after real training.”
The room went quiet.
“Proper sustenance?” It was Uraraka who spoke.
“You all push your Quirks to the limit, but your bodies are underdeveloped in comparison. You rely on your Quirks, not your own strength.” Urokodaki continued as Rengoku loudly praised the food. “When you were forced to train without them, you burned through energy faster than you ever have before. Your bodies now crave what they need to recover.”
Uraraka remembered what Himejima had said. That their bodies were not stable, that their attacks were not as accurate as they could be. That when they defended that it took too much energy, that they would get fatigued too easily. So he had them do basic exercises at first in order to strengthen their bodies as his own advanced training was going to be a hundred times harder.
“Shinazugawa-san, instead of just chasing them you can always show them what you can do.” Hanako suggested looking at Sanemi who looked to the side. “Look, I know you’re worried about them… except for Todoroki. You can’t see him as Tomioka-san, but like Tomioka-san there is another side underneath that arrogant and aloof demeanor. I know what I said earlier about you treating them like you would your own students, but… try to at least teach them before you terrorize them.”
“If they want to be heroes they're going to have to learn to take a hit or out maneuver it!” Sanemia snapped.
“You’re also teaching them Wind Breathing, this isn’t just Hashira Training. This is Wind Breathing Training.” Hanako pointed out and Sanemi went quiet after that. “You know… Kanae would want to see how well you can train them.”
Sanemi looked like he was going to murder her after she brought up his crush. However she had made her point, if he was going to be stubborn she was going to bring in the other Hashira, and perhaps the Oyakata; Ubuyashiki Kagaya. The reason why they managed to get this job. Ubuyashiki and Nezu had come to an agreement. Ubuyashiki had shown records that Demon Slayers were heroes, they were just never acknowledged by the government.
“Fine, I’ll make sure they get the basics in them before beating them until they drop.”
“Much better!” a voice at the door said and everyone’s head turned seeing the rest of the Hashira, including Kanae standing there. Kanae was smiling as Sanemi glared at Hanako. “Oh, we actually needed to move in… the house also collapsed.”
Silence, then the realization kicked in that they were going to be living with the Hashira.
“So does that mean you’re going to use all of the empty rooms?” Mineta stumbled over his words as Sanemi glared at him. “Did Principal Nezu even approve of this?”
“No, actually, unlike you guys, they’re sharing the rooms.” Hanako said before she spotted Mitsuri and they both bounded over to each other and said hello with a hug. Mineta was staring at Misturi’s chest before Obanai noticed. He shared a look with Sanemi and nodded his head. Sanemi returned the gesture. Hanako cleared her throat before gesturing to the building. “They still need to do their homework.. And yes, Nezu did.”
Once dinner was done, they went and took a bath, getting ready for bed as they did so. Hanako actually taught them the remainder of the lessons that they missed for the day in the dorms.
The next morning, at four, Hanako was sipping tea. Four out of the five Hashira trainers were going around waking everyone up. Sanemi was on breakfast duty. She figured it was best to rip the bandaid off, not to cause the wounds to get worse. Kanae was standing next to Sanemi, whose ears were pink. Shinobu looked like she wanted to pick on him but Hanako kicked her under the table before shaking her head. Sanemi was being quiet, the students were going to have their own wake up.
“GOOD MORNING! TIME TO RISE AND RESUME YOUR TRAINING!”
“GET UP! YOU’RE NOT TRAINING TO BE LAZY!
Screams from the floor Urokodaki was on, then knocked on the door for the girls, then more water was splashed over them when there was no response.
Himejima’s calm voice was too far away since he was on the fifth floor.
They claimed their floors because of who was on them.
Rengoku- 2nd Floor: Mineta Minoru, Midoriya Izuku, Aoyama Yūga, Tokoyami Fumikage
Urokodaki- 3rd Floor: Kōda Kōji, Kaminari Denki, Īda Ten'ya, Ojiro Mashirao, Jirō Kyōka, Hagakure Tōru
Kuwajima- 4th Floor: Shōji Mezō, Kirishima Eijirō, Bakugō Katsuki, Uraraka Ochako, Ashido Mina
Himejima- 5th Floor: Satō Rikidō, Todoroki Shōto, Sero Hanta, Yaoyorozu Momo, Asui Tsuyu
“Morning everyone!” Hanako greeted as they were being filed out as she went to take over breakfast from Sanemi. “Breakfast will be served after your early morning training.”
There were complaints but Hanako interrupted. “We don’t want you throwing up.”
They were promptly taken outside to start their early morning workout routine under the watchful eye of all the trainers.