My Own Infinity Battle (Demon Slayer OC)

Chapter II: Preparing for battle (part 2)

"You have come, so let's begin!" Yūkan said and charged at them
"Wai-" Gakusei was trying to say, but Kaoni grabbed him and jumped to dodge Yūkan attack.
"Thanks, Kaoni" Gakusei said and they were looking at each other and Kaoni just nodded her head. Both of them drew out their swords
*It can be hard, we didn't train to fight with swords and he was sure, it couldn't be worse*. Gakusei was trying to think of a plan but Yūkan attacked again but this time Kaoni parried his attack with sword. Meanwhile Gakusei was just standing uselessly in one place.
*Why can't I move?! Damn! MOVE!*
"What Gakusei? Are you really scared so much you can't move?" Yūkan said but then Kaoni used that moment to push him away. So Yūkan rushed again, and when he was just in front of her, he dodged around behind her.
"One down" Yūkan said and raised his sword for final blow when Gakusei blocked the upcoming attack.
"So you have decided to fight, huh? So be it" Yūkan said and attacked him from below, but Gakusei deflected it away and started to attack from multiple angeles. Yūkan managed to defend himself but was slowly forced back.
"Nice but... you fight with more than a sword" Yūkan said and he kicked Gakusei so Gakusei was now on his knees.
"This time you will not live long enough to see next sunrise" Yūkan said and he went for an attack but Gakusei somehow was able to dodged it and when Yūkan want to try again Kaoni attack him from behind... again.
"Gakusei, stay here" Kaoni ordered but Gakusei was still trying to get up, but then he felt a immerse pain in place where Yūkan had hit him. So he could just watch and see Kaoni jump on a tree, and attack Yūkan and retreat to the trees covering the landscape. Kaoni was doing it several times.
"Good, I expected that you will be good, but you Gakusei! I'm disapointed. Did you forget everything what Shinda taught you?"
*What Shinda taught me? But she didn't teach me anything. I had do it on my own!* Gakusei thought
"I just don't want to fight my sensei" Gakusei said
"It doesn't matter who I am. You must fight even if your opponent is a member of your family. And now we will start training with katana, because this fight was only to test your abillites"
Yūkan said and they started training. They started with basics. Then how to kill demons efficiently. How to use your surrundings to your advantage. After months of training and sparing against each other. Gakusei was doing his best all the time but still, even after that training he couldn't surpass Kaoni. She was better at everything. Even when Gakusei was trying to copy her attack he still wasn't good enough. Therefore he was losing his sleep to go outside to train. This time is the same situation. He left the house and start training everything Yūkan had taught him. He was doing it for some time and satisfied he decided to take a short break.
"You still here? You don't like to think, huh?" Gakusei heard a voice.
*Who is that? Demon? No* Gakusei thought
"Where are you?! Who are you?!" Gakusei said
"Calm down Gakusei. It doesn't help your training" someone said behind Gakusei and he felt someone's hand on his arm. Gakusei slowly turned around and he saw Yūkan
*Se-sensei?* Gakusei thought
"You know. Have you ever thought about why she is better than you? Have you been watching her carefully? I will tell you something. Kaoni isn't better than you, she is scared of demons. Maybe it doesn't look like it but she had run from final selection 3 times. This is why you are here today. Kaoni once said to me that if she runs again she ends her demon Slayer training and is going to just go back home. You are here to prevent that from happening. You really should be thinking and watching more. The key is not to just stand your ground. The key is to never surennder and with each time you learn sth you practise to become the very best human" Yūkan said without even looking at Gakusei he was looking foward and then he disappeared
*No surennder, huh?* Gakusei thought and he sit on grass. Then next to him he saw a book. He picked it up and he started reading
*Regenerate breath?...full concentration breathing? What is it* Gakusei thought and then continued
*They are so powerfull because of how they breath?! I must try it* Gakusei thought.

The next few days passed and Gakusei was still losing, but Yūkan said to him not to surennder so he won't do it. And finally after months of fighting and training he wins. Because finally he mastered regenerate breath and total concentration breath. The next day Yūkan said to them
"you are finally on same level i will teach you breathing styles. And I don't mean like regenerate breath I mean something else. Yūkan said and he started explaining to them about all of this. When he finished his lecture he then said
"I want you to create your own breathing style"
"O-own breathing style? But how?" Gakusei tried to say
"I will teach you the basics but most of the work you have to do yourself" Yūkan said
"Listen, now we will begin with something easy. This what you will do here will be your first technique. Remember, every technique should be able to kill in one moment. And for now it doesn't have to be too strong it's just a beginnig. Kaoni you start because you know better how to do it." Yūkan said and he brought mannequin of demon. Kaoni just approach it and quietly says
"illusion breath, first form: false leaf" Gakusei looked and thought
*She does the same thing when we were fighting with Yūkan. She just jumped and attacked from diffrent angles she use her speed. I should use my good sides to i guess*
"Now you Gakusei" Yūkan said when Kaoni have ended. Gakusei came over and looked at it
*What would be the best spot to attack? Head for sure, but if that one attack doesn't work all technique fail hmmm...what am I going to do?* Gakusei have thought and then he got his katana near to it and started at first slowly attacking leg, but tried not to cut it off. Then a hand, head and after that hand and leg on the other side. Gakusei looked what he just did
*That looks like Infinity signs so...* Gakusei thought and then he jumped backward and rushed and was waving his katana back and forth as fast as he could. And in one moment mannequin have had cut hands, legs and head.
"I see...anyway now start do it over again." Yūkan said
After hour of training he said
"Next day we are doing a diffrent technique. But remember that, breathing should be compatible with your fighting style. It will help you to use your good sides in fight. And now go to sleep it's getting dark." Yūkan said and they go back to house. But Gakusei had diffrent plan. So after everyone were asleep he again went to train everything what Yūkan told him, but after a while he stepped back breathing hard
*its...its harder than i thought* Gakusei stuttered and then he got into position and he started again
*i-infinity breath, first form: Infinity charge* he thought and he rushed again and over and over. After that he was tired a lot. He then heard someone near him. So he looked around, but he Finder no one. Then he heard an evil laugh
"Finally someone who won't be hard to eat. This place is always guarded by someone but it looks like I'm lucky today."
"Where are you?" Gakusei said but no one answered him then he heard something jumping to him from behind, so he tried to block it by sword but demon just pushed him far away.
*Damn, i-im to tired, i cannot do anything.* Gakusei thought while breath heavly
"Well it ends now. Don't worry i will end it quickly" demon said and he dashed to him. Gakusei thought that it was his end so he closed his eyes. Then he heard swish of a sword but didn't feel any pain. He slowly opened his eyes and saw Kaoni sheathing the katana.
"You saved me....thank you" Gakusei said
"Yeah, and now come, you should rest" Kaoni said to him
" you are probably right" Gakusei said and sit under a tree.
"So what are you doing here at this hour?" Gakusei asked
"I want to talk to you, and i knew where to find you" she said
*Was she really following me this whole time?* Gakusei thought
"I see...so what do you want to talk about?"
"About...Shinda Difendā" Kaoni said
*She knows about her? Even her full name?* Gakusei thought
"How do you know about her?" Gakusei asked as he tried to look unfazed but in reality he was not, it terrified him
"First time i heard about her from you" she said
"What? How? When?" Gakusei asks. now he is suprised
"I couldn't sleep because you were talking 'Shinda-sama, Shinda-sama, Shinda-sama." She said and Gakusei blushed a little.
"Anyway, I tried to ask Yūkan about her but he didn't tell anything important. So I got a look on his notes. I know that because of her you are here but... looks like she is working for demon Slayer corp. But I think she isn't a regular Slayer, she more trades because they are paying her for something more than killing demons...and it's not something like weapons or something like that. Its something more beacuse if it was something normal they wouldn't hiding it." She said and Gakusei punched her, and Kaoni fell to the ground
"You don't know her, so don't talk about this" Gakusei said coldly and didn't even look at her, and he was gone. Gakusei came back to bed and he tried to sleep
*How actually Shinda knows Yūkan? I must to find out* Gakusei thought and he go to sleep
Next day was just a normal training. Kaoni was peaking at Gakusei but he was focused on training. Like he wanted to forget about all of this.