Currently, Y/n was walking to the Academy with Erza, he was thinking about the events that had transpired the day before.

(Flashback)

Rias: Holy Swords are the most dangerous weapon against the devils. Simply by touching one burns a devils body and most importantly, being cut by one means instant death to the devils. The truth is a holy sword can annihilate a devil.

Issei: There is one question I do have about possibly negating the effect. Would Haki work?

Y/n: Yes it does, I've been attacked by Holy Sword users before and using Armament Haki does decrease the effects greatly but not entirely.

Issei: Interesting, still sounds a bit intense though.

Rias: It is. The fact that those who can use one are extraordinaryly rare is the biggest weakness of the holy swords. The church tried what they could, they tried to raise people artificially. 

Erza: We believe it was to allow people to wield Excalibur.

Issei: Like King Arthur Excalibur?

Y/n: It's a phony compared to the real power of one...

Issei: Huh?

Erza: Many years ago, me and Y/n met the Real King Arthur, or well the spirit of her.

Issei/Asia: King Arthur was a Woman?!

Y/n: Yep, Artoria Pendragon, what a woman she was. Anyway, we should mention the Holy Sword Project.

Issei: Holy Sword Project?

Asia: The church must have kept it a big secret, because I've never heard of it.

Rias: It does make sense, it's in the past now. I heard the project was a complete failure.

Y/n: It was...

Rias: And Kiba was the only survivor.

(End of Flashback)

Erza: You alright Y/n?

Y/n: Yeah, I'm fine, just thinking about something.

Erza: Alright, tell me if you need to.

Y/n: Will do.

The two continued walking, when they both stopped walking, the two looked at each other and nodded. The two then rushed to the Academy and they saw three white cloaked figures. One with something wraped on their back and another one with a metal pipe and they were talking to Sona and Tsubaki. After a bit, they walked away and Y/n and Erza walked up to them.

Y/n: You two okay?

The two of them turned around to see Y/n and Erza.

Sona: Yes, Y/n. We're fine.

Erza: Members of the Church?

Tsubaki: Exactly.

Sona: They walked to talk to Rias and You two about something.

Sona: About something very important. But they didn't tell us what.

Y/n: I have a strange feeling I already know...

(Timeskip)

It was currently lunch time and Y/n was underneath a tree eating a bento box he had made that morning, he would normally eat with Erza, but she was eating with the Kendo Club. Y/n then heard footsteps and looked over and saw Koneko.

Y/n: Sup Neko.

Koneko: Hey Y/n. Mind if I join you?

Y/n: Sure, be my guest.

She then sat next to him and started to eat her lunch, Y/n being Y/n put his Straw Hat over his face and fell asleep, but a few mminutues later, he heard girls talking, waking him up.

Girl 1: That's so cute!

Girl 2: That's adorable.

Y/n removes the Straw Hat from his face, he then looks down and a small smile appears on his face. He saw Koneko sleeping and she was curled up in his lap.

Y/n: Now ain't this adorable.

Koneko then got more comfortable on his lap.

Koneko: Warm...

Y/n then began to rub her head.

Y/n: Sleep well Kitty.

She smiled in her sleep.

(Timeskip)

After school, Y/n, Erza, Issei, and Asia made it to the old school building and they were surprised at how clean it was.

???: Yo what's up guys.

The group turns around to see Ace walking towards them.

Y/n: Yo Ace, nice of you to join us.

Ace: Yeah, had a weird feeling I needed to be here today.

Issei: Nice to see you again Ace-sensei.

Ace just smacks him on the back and chuckles.

Ace: None of that, just call me Ace.

Issei: H-Hai Ace.

Asia: Look how shiny the floor is.

Issei: I think it's too shiny....

 Y/n: Yeah....

Erza and Asia turned to them.

Erza/Asia: Something wrong?

Issei/Y/n: Nope.

The five of them continuted to the clubroom and Asia saw a set of doors with yellow tape and chains around it.

Asia: Hey, what's in this room?

Issei looked at the doors, while Y/n, Erza, and Ace pretended not to notice.

Issei: No clue. Rias said it was the forbidden room, and it's never been opened.

Meanwhile, Y/n, Erza, and Ace were talking mentally.

Ace: I wish we could tell them about him.

Y/n: I know, I know, but he still can't control his power and he doesn't want me and Erza to help.

Erza: Our poor boy....

Ace: How long has it been since he's seen his sisters Meteion and Tsuki?

Y/n: Too long...

The five of them made it to the club room and saw Rias and Koneko, Y/n and Issei looked around, not seeing Kiba.

Issei: Where's Kiba?

Koneko: He's not here. I didn't see him at school either.

Ace: Let me guess... It's about the Holy Sword Project?

Issei: You know too Ace?

Ace: Everyone in Y/n's peerage and even his familars know about it.

Issei: What is his fixation with Holy Swords?

Rias: Do you remember what I said about him being the only survivor of the Holy Sword Project?

Issei: Yeah...

Y/n: All of the others were raised to use The Fake Excalibur...

Issei and Asia look at her shocked.

Erza: As of right now, they're are Seven Holy Swords that are known by the name "Excalibur". Long ago pieces of the original Excalibur were scattered during a war.

Issei: Seven?

Rias: That's right. It was the church that hunted them down and collected the pieces. They then used alchemy to create several entirely different swords.

Issei: I assume Kiba can't use any of them?

Rias: You are correct. He never adapted to their strength. In fact no-one of those who were trained ever could. The project completely failed.

Asia: Completely?

Y/n: Yes... Those bastards in charge of the project decided to dispose of Kiba and the other test subjects...

Issei: Oh please don't tell me...

Rias: Yes. They killed them. They were already on the verge of death. However, one child was able to escape. His motivation to stay alive was a promise to himself that someday he would get revenge. I felt that such a passion could be used in a meaningful way and wanted to help. There was but a single solution.

Issei: So that's why he's a devil, it all makes sense now. His reaction the to the picture was sketchy at first, but not it's clear.

Rias: We'll just have to wait and see what happens next.

The door opened and Akeno walked into the room.

Akeno: Fantastic. Looks like everyone is here.

Rias: Akneo, why are you so late?

Akeno: Well, I brouigt some company and thought I'd help them get there.

Sona and Tsubaki both walked into the room.

Sona: Thank you for having us.

Issei: Sona and Tsubaki-senpai? Why are you two here?

Akeno: They said they had something important to discuss with Rias, Y/n, and Erza.

Sona: Right. Rias, Y/n, Erza, would you three mind coming with me to my house right away please? This isn't something you want to discuss in front of a lot of people, trust me.

Rias: You make it sound like a complex situation.

Sona: It is. Very complex.

(Timeskip)

After Rias, Akeno, Y/n, and Erza went with Sona and Tsubaki, Issei and Asia started to make their way homem. And as the duo got closer to Issei's house, Issei felt a pressure and stopped.

Asia: Is everything alright?

Issei: Stay behind me, there's holy magic coming from the house...

Asia: WHAT?!

Issei: Proceed with caution. We don't know what's in there. Come on.

The two of them made it back top Issei's house and when they did, they heard Issei's parents talking and laughing.

They two of them walked in and saw them talking to two cloaked figures that Y/n had seen that morning. However, Asia's eyes began to tear up, behind the two figures was a man wearing a top hat with a metal pipe on his back, he had blonde hair and a burn scar, when he noticed Asia he smiled.

???: It's good to see you again, Little Sister.

Asia: SABO!!!!

Asia quickly ran over and hugged Sabo happily, as he did the same smiling.

Sabo: I missed you too, sis.

???: Oh I love reunions like these.

???: Hmm....

Issei then looked at the other girl on the couch and his eyes widened.

Issei: Irina?

Irina: Oh you actually remember me?

Miki: I know, she looks different. I mean you could've mistaken her for a boy if you didn't know better.

Issei: Not to be rude, but I honestly knew you were a girl, but you acted like a real tomboy back then.

Irina: I suppose I did.

Asia: Sabo....

Sabo: I already know little sis.

Asia: That I became a Devil?

Sabo: I was surprised at first. But I refuse to turn my back on you, I made a promise to your mother that I would protect you. If this is your choice, then I am okay with it.

Asia: Thank you, Big Brother.

Asia then hugged Sabo one last time and he smiled.

Irina: Aww, so cute.

(Timeskip)

After Xenovia, Irina, and Sabo left, Issei and Asia went up to Issei's room, being met by Rias, Y/n, and Erza. Rias got up and she hugged the two of them.

Rias: I'm glad you're two are home safe. I'm so sorry. I should have paid more attention to the two of you. I was terrified from what I might find when I came back here. I'm thankful I'm worried for nothing. I promise to keep better eye on the two of you.

Issei: Umm, Rias?

Rias: What it is?

Issei was blushing like crazy.

Issei: I don't wanna sound like a perv, but umm....

Rias quickly backs away from the hug with a blush on her face while Asia pouts with Jealousy.

Rias: Alright then, but why were they in there talking to your mother?

Issei: Most likely Irina wanted to catch up with my mother, but I have a feeling it's something else.

Rias: Most likely. We will just have to ask them tomorrow.

Y/n: Issei, you and I need to speak. Do you two mind if I take him to the other room?

Rias: Of course, just make sure to bring him back.

Y/n: Of course I will. Follow me Issei.

The two of them made their way to Y/n and Erza's combined room. Y/n went over to their bed and pulled out a very long case.

Issei: What's in the case Sensei?

Y/n didn't speak he walked over to Issei and opened the case, inside of the case was a katana, but not just any Katana.

Issei: I-Is that?

Y/n: Yes this is my former sword, this is the sword I used before I got Enma. It's name is Shusui, it is one of the 21 Great Grade swords and is known as a "Black Blade". You have shown tremendous growth in your time as my student, and I believe it's time for you to learn the blade. 

Issei: B-But...

Y/n: No buts Issei, I want you to have this sword, I trust in you that you can use it well.

Issei gently picks up the Katana before unsheating it, the black blade showing his reflection in it. He then resheathes the sword and attaches it to his hip.

Issei: I'll use it well Sensei.

Y/n: I'm glad, now while I believe in you, I don't think my sword style is meant for you, I believe there is a much better sword style for you, so tonight in your dreamscape, you will be visited by someone who I think will teach you the perfect sword style.

Issei: H-Hai Sensei!

Y/n puts a hand on his shoulder.

Y/n: You've earned the right to call me Y/n, as a fellow swordsman.

Issei: Thank You, Y/n.

Y/n: Anytime, my friend.

(Timeskip)

Later that night, Issei was asleep, he then opened his eyes to see he was in an old school japanese house.

???: You must be the one Y/n spoke of. It's nice to meet you.

Issei turns around and is greeted by someone.

Issei: Ah yes I am, are you who will be training me how to fight with a Katana?

???: I am, I looking foward to training with you.

Issei then bows and summons and Shusui.

Issei: Shall we begin?

???: We shall.

(Another timeskip)

After school, everyone besides Kiba, Y/n, Ace, and Erzxa were at the club room and they were all standing behind Rias, as she sat in front of Irina, Xenovia, and Sabo.

Xenovia: Thank you for agreeing to speak with us today. My name is Xenovia

Irina: My name is Irina.

Sabo: Sup, name's Sabo.

Rias: It's interesting that followers of God, would want to meet with a devil.

Irina: It does seem random, but here's the thing. There are six swords we can account for.

Sabo: We have three with the church, but we happen to know that the other three were stolen by Fallen Angels.

Issei: Are you sure?

Xenovia then lifts up the object she had wrapped up in cloth.

Xenovia: These are the ones we have left. They're made from Excalibur. This one is mine, it's called the Sword of Destruction.

Irina: And then there's the one I have here. It's known as the Holy Sword of Mimicry. It's an Ecalibur Mimic.

Everyone then looks at Sabo. He looks at them confused.

Sabo: What?

Rias: Don't you have one, that pipe of yours?

Sabo: This is just a metal pipe.... Made of out of Nichirin....

Rias: Well, what it is you would like us to do for you today?

Xenovia: Stay completely out of it. This is between us and the Fallen Angels. Let's keep it simple, shall we? We don't need the Devils in this town to interfere.

Rias: That sounds like accusation ,are you afraid that we side with the Fallen Angels? And keep you from them?

Xenovia: And if that's ture, then we'll have no choice but to completely destroy you. Even though you are the sister of a Great Devil and a Yonko Maou.

Suddenly, the door the the ORC opens to reveal Ace, Y/n, and Erza.

Erza: Our apologies for being late.

Ace: Yeah, Y/n decided to stop for do-

Y/n: Hey I was just hun-

Ace and Y/n freeze in place as they stare at Sabo, who stares back at them. Tears then begin to well up in Y/n and Ace's eyes.

Ace/Y/n: S-Sabo?!

Sabo then smirks.

Sabo: Hey you two, been a while.

Y/n then stretches his arms out and wraps them around Sabo's neck.

Y/n: DO YOU HAVE ANY IDEA HOW MUCH WE'VE MISSED YOU, YA BIG IDIOT?!

Ace: YOU'VE BEEN MISSING FOR OVER A DECADE!

Sabo eventually removes Y/n so he can breathe.

Sabo: Sorry about that, I just got busy.

Everyone minus Erza: What is going on here?

Erza: It's Simple. Ace, Y/n, and Sabo all grew up together, Y/n is the youngest out of the three of them. So they are pretty much sworn brothers.

Sabo: We even had the sake cups and everything.

Ace: Man was Y/n's mom pissed when she found out we had stolen some from her supply.

Y/n: I couldn't feel my ass for a week! She gave me 10000 spankings!

Xenovia: Could we get back to our meeting?

Y/n: Oh yeah sure.

Rias: As I was saying, there is no way I would ever think of joining the Fallen Angels, I would never do anything to ruin the name of the house of Gremory or my dear brothers.

Xenovia: It's enough for me to hear that. I was only relaying the thoughts of headquaters, I honestly didn't think the little sister of the great Devil King would really be that stupid.

Rias: Good to know. I hope you also understand that I will not give aid to your side either.

Xenovia: Of course. I trust we will prevail if you promise not to interfere with anything we may do in this town.

Rias: You have my word on that.

Xenovia and Irina got up, while Sabo was still chatting with Ace, Y/n, and Erza.

Xenovia: We won't take up anymore of your time.

Sabo then turns around.

Sabo: Did somebody say-

Xenovia: No thanks, I'm not here to make friends with Devils. We'll let ourselves out.

Sabo just sighed.

Sabo: I'll catch up with you two later, I'm gonna hang out here for a bit.

Xenovia: Do as you wish. 

She and Irina started to walk out but Xenovia stoipped and looked at Asia.

Xenovia: I was wondering if visiting the home of Issei Hyoudou would lead us to you. Aren't you Asia Argento?

Asia: Yes, I am.

Xenovia: It makes sense that I'd run into a witch in a place like this.

Irina: Oh my goodness, it is you. You're the former saint who became a witch. I had heard you were banished because you had the power to heal Fallen Angels and Devils and at one time you actually used it. You most be pretty strong. I didn't know you actually become a Devil yourself.

Asia started to look down nervously and Sabo and Issei Noticed.

Issei: Asia, are you okay?

Xenovia: No, she isn't. She went from being a saint to being a Devil. That's about as far as one can fall.

Sabo: I suggest you stop Xenovia.

She ignored him.

Xenovia: Do you still believe in our God, Asia?

Irina: Don't be silly. She's a Devil, she's over us.

Xenovia: No, that doesn't always mean what you think it does. There are those who's hearts continue to stay loyal amongst their own betrayal. She seems like she may be one of them./

Irina: Really? Is it true, Asia? Do you still believe in God? I mean I know you're like a devil, but do you.

Asia: I do, I was never able to let go, I still believe In God and will continue to do so.

Xenovia: Then you should allow us to-

Before Xenovia could finish her sentence, she felt an overwhelming prescence, but it wasn't from Y/n, Erza, Sabo, or Issei. It was from.....

Asia herself.

Y/n: H-Has she been training with Nami in secret, that's Nami's stare when she's pissed off! I haven't been this scared since she reunited with Zeus...

https://youtu.be/dzngaURznSg

A/n: Here's some context to that statement. Nami makes me scaroused...

Asia: You going to tell me you want to kill me? There's a lot of people who have told me to kill myself over the years, ever since the church wanted to kick me out, Sabo was the only one of them who stood up for me, I'm tired of being that weak little girl, if you want to kill me so bad, I won't go down without a fight, even if I have to fight off the whole church!

Issei: H-Holy shit...

Sabo: My little sister became a badass!

Asia then turned and glared at him and Sabo froze.

Sabo: S-Shutting up now!

Xenovia: So you are prepared to fight the church? You know you won't stand a chance against us.

Issei then walks next to her.

Issei: She won't be fighting alone, I'll fight by her side.

???: This is perfect, I'll take all three of you.

Everyone turned around and saw Kiba leaning against the wall.

Xenovia: And you are?

Kiba: Your superior. Pleasure to meet you.

Y/n: Aw crud, here comes the fight....