Complete Set

Before I start this chapter, some of you might be wondering why this fanfic is a major crossover with The Devil Is A Part-Timer if we haven't seen any characters from that universe. The answer is simple: They will appear around Chapter 32 ish.

('Ddraig speaking telepathically')

("Ddraig talking out loud")

['Albion speaking telepathically']

["Albion talking out loud"]

{'Bahamut speaking telepathically'}

'A character's thoughts'

Asgard

"Hello Gabriel. By your report, the Sekiryuutei is worthy?" Spoke Odin.

"Indeed, Lord Odin. Although, I am sure you already are aware of that. He singlehandedly killed Kokabiel, a mid-high ranking Khaos Brigade member and former Fallen Angel leader. I believe you should be the one to train him."

Thor leaned forward. "No offense, but how do we know you're not just saying this because he is dating your daughter, who also happens to be his Queen?"

Gabriel smiled kindly with her eyes closed, but behind that smile was something threatening. 'You dare to insinuate that I would play favorites with Issei? Fufu. How amusing.'

"I don't play favorites, Lord Thor, but let me be honest with you and say that I do owe the Sekiryuutei a great debt since he killed the man who tried to kill my daughter. I am sure you would do the same thing if someone were to attempt to hurt your mother, whom you care for tremendously. Am I wrong?"

Thor's eyes widened. "... No. You're right."

"Thor, I do suggest that at some point in the future, you should try to get to know the Sekiryuutei yourself, at least through your own observations. I actually think the two of you could make great friends."

. . . . . . .

The Underworld

"Sirzechs, there is something I need you to see."

Sirzechs was in the middle of a meeting with the other three Great Satans, discussing the Khaos Brigade, when Issei Hyoudou suddenly teleported in with Kuroka Toujou.

"Oh wow! So you're the Sekiryuutei!" A green-haired man said. "My name is Ajuka Beelzebub."

"I'm Falbium Asmodeus." A bald man stated boredly.

"And I'm Serafall Leviathan. You go to the same school as my little sister, right?"

She received a confused head-tilt. "Wait, who?"

"Sona Sitri is my little sister."

Issei's eyes widen. He nodded. "I see. I'm not too surprised. Sona is someone I consider an ally. Anyway, I'm Issei Hyoudou. I'm here on both personal and official business."

Issei handed a book to the Satan. "This is Kuroka Toujou's diary. I rescued her little sister, and in doing so, she promised that she will join my peerage."

Sirzechs raised both eyebrows, confused. "Why are you telling me this?"

"That diary holds information that will exonerate Kuroka of all the crimes she has been accused of."

Issei furrowed his eyebrows. "Seriously, I don't mean to be rude, but I'll be straight-forward with you by saying this: it is very infuriating to hear that she wasn't even given a trial. You people are the leaders of your race, right? Then start acting like it instead of going on a witch-hunt and trying to crucify someone when none of you would hear her plight."

"Issei, we live in a society where-" Sirzechs began, but Issei cut him off.

"No! No shit. A society?! You don't say! How could I not have noticed?!" He exclaimed dramatically, voice dripping with sarcasm.

The Sekiryuutei turned serious as he glared at all of the Satans, which made them flinch. "You Devils need to get with the times and start treating everyone as innocent until proven guilty beyond any shadow of a doubt, because if you don't change, I will force you to for the better. Oh, and remind me again what happened the last time your kind forced the hands of the Dragons? Didn't you almost go extinct?"

While Falbium snored in his sleep, the other three Satans narrowed their eyes at Issei.

"Is that a threat? If so, your power has gone to your head." Asked Sirzechs.

Issei snorted. "That's funny coming from a Gremory. It's not a threat, it's a promise. Every now and then, a violent revolution against those who govern a society is needed, even if the rogue elements invade from the outside. Sirzechs, you and Leviathan-chan are the only Devils outside those in my peerage and circle of friends that I trust. Clear Kuroka's name."

Sirzechs flipped open the diary and began reading out loud. The writing is barely legible as it is nearly a decade old.

'Today, I killed my master. I feel awful. I feel sick to my stomach, but it was the right choice, and I would do it again (28). The reason I did this is to protect my little sister, Shirone. Master was going to experiment on her to try to create a Super Devil. I hope that I won't get in trouble for this and that everyone understands, especially Shirone.'

Next entry.

'Shirone says she hates me. I can't blame her. After all, I killed our master right in front of her, and because I used Senjutsu, Shirone proclaimed that she will never use the supposedly accursed power. She's terrified of me and herself. I've also been labeled a stray Devil, even though it has only been a couple hours since I did the deed, meaning they didn't investigate thoroughly. With the way Devils operate, they won't hesitate to try to kill me as punishment for something that I didn't do, so I will have to always be on the run. I don't think I'll trust any Devil ever again.'

The words, "ever again" are crossed out and replaced with, 'for a very long time.'

Next entry.

'Please forgive me, Shirone. I would kill that man again and again if it means protecting you, but I didn't mean to traumatize you. I'm so sorry.'

Final entry. This one is much more recent than the previous ones.

'I am about to willingly joined the peerage of the Sekiryuutei Issei Hyoudou as payment for him rescuing Shirone, who was kidnapped by Kokabiel, the same lunatic that the Devils have been letting run loose and commit violent acts for a very long time. At this point, I am not surprised since they turn a blind eye to their own race enslaving people, fellow pure-blooded Devils and reincarnated ones formerly of other races. Well, whatever. I can finally get rid of this filthy Devil blood in my veins and replace it with Draconic blood. Issei is also going to give this diary to the Satans. Just like Shirone, and kind of like that Himejima girl, former Queen of Rias Gremory, I also somewhat hate myself for what I am, and now, I will finally be free.'

Serafall was horrified, her hands covering her mouth. "Oh my god, what have we done?" She said softly.

Sirzechs nodded in agreement, a sad look in his eyes. "We need to fix this. Before you leave Issei, Kuroka, Ajuka has a method that can immediately exonerate her."

Issei smiled. "In that case, take a seat, Kuroka."

Kuroka sat down in front of Ajuka. "What method is it?"

Ajuka pulled out a small object and set it onto the table. "This here is a magical bell. It will ring when the person being interrogated lies to the question. This conversation will also be recorded as a video via magic as soon as you are ready." (29)

Issei smirked. "Oh? Let me ask you a couple questions to test it." He cleared his throat. "Are most Devils like old people who refuse to acknowledge major problems in society, instead choosing to force the issues down the line for future generations to take care of?"

"Well, I wouldn't necessarily say that," Ajuka sweatdropped.

DING!

"Next question: Are most Devils full of shit?"

"Y-Yes."

Silence.

"Final question, and I want you to count by numbers for each answer you get wrong, increasing by one: How many girls have feelings for me or find me attractive, not including my many fans?"

Ajuka sweatdropped while Sirzechs and Serafall struggled to not laugh at him. "Um... Three?"

DING!

"Four."

DING!

"Five."

DING!

"Six?"

DING!

"Seven?!"

DING!

"Eight?!"

DING!

"Nine?!"

Silence.

Issei's eyes widened. 'Nine?! That's the number of people I can have in my peerage since I have seven right now, am about to add Kuroka, and only need one more Knight after that for a complete set!'

('Uh oh. Me thinks a certain Sensei has fallen for you, partner.') Ddraig teased.

'I doubt it since Rossweisse is a teacher and probably finds a student-teacher relationship with an underage boy such as myself to be taboo, but I'll have to ask her at some point. I wonder who the other person is?'

Issei nodded at Ajuka. "Alright, carry on with the interrogation."

"I am ready," Said Kuroka as Ajuka began filming it.

Ajuka cleared his throat and looked at Kuroka. He showed the diary to her. "Is everything you wrote in this diary true?"

Kuroka nodded. "Yes, nya."

Silence.

Serafall lowered her head. "I... I see. We will immediately begin working on clearing your name and releasing an official statement."

"Eh? We will?" Sirzechs asked, recieving a hard smack on his head from the twin-tail loli.

. . . . . . .

The Next Day

"Lie down for me, Kuroka."

"Nya, put it in me, master~"

( ͡° ͜ʖ ͡°)

"Okay, here I come!"

Issei put the Bishop piece on Kuroka's chest. The golden piece glowed as it turned green and disappeared inside her.

Chapter 12: Complete Set

Tuesday, September 29, 2020

Kuoh Academy

"Alright class, we have four new transfer students. Our class is now at max capacity with 45 students, so we won't be able to accommodate anyone else. Please give them a warm welcome," Rossweisse said.

Four people walked in, all of whom Issei recognized.

"Please introduce yourselves."

"I am Mittelt. I-It's not like I want to be friends or anything!"

"Ah. Tsundere character." - Every guy.

"H-Hello. My name is Asia Argento. I am from Italy. Please take good care of me!"

"My name is Kalwarner. Please treat me well~"

"HER BOOBS ARE HUGE!" - Every guy except Issei.

"Hello, my nyame is Kuroka Toujou, nya. My younger sister is Koneko, nya. I am one of Issei's seven girlfriends in his harem. Nyice to mweet you, nya."

"Issei, you bastard!" All the boys except Vali yelled.

"Seven girlfriends?! Kya! I wish I was one of them!" Some of the girls exclaimed.

Issei's latest peerage member and newest Bishop, Kuroka, had just transferred into Kuoh Academy. She is also in his harem, but announcing his harem to everyone gave him a headache.

"Ask them a few questions one at a time," Rossweisse ordered.

Katase raised her hand and asked, "What are your last names, if you don't mind me asking? We already know Argento's."

Kalawarner replied, "We're friends with Raynare, and like her, we grew up as orphans on the streets. Luckily, we live with Issei now since he was kind enough to offer us a home."

Issei was surprised and whispered to Raynare, "Are they moving in?" He received a nod and a kiss to the cheek, making Issei almost scream and Raynare giggle.

Motohama raised his hand. "Who exactly is in Issei's harem?!"

"Nya? Oh, that would be myself, Raynare Hyoudou, Arisu Yamauchi, Akeno Himejima, Natsuki Murayama, Irina Shidou, and Ravel Phenex... I think."

"The bastard stole Akeno-senpai?!"

"I still can't believe he took Ray Ray!"

"Not just the Kendo Captain, but Yamauchi too?! She won't step on me any longer! No!"

"Oh my god!" Another guy yelled in Engrish. "Hory shit!" (30)

The girls chimed in too.

"Wow! He's way cooler than Kiba!"

"I know, right?! He's so hawt!"

Issei smiled at them confidently, earning squeals from the girls not in his harem while Irina pouted at the female attention her King is receiving.

Rossweisse silenced everyone. "Toujou, you may sit wherever you want."

Issei sent a telepathic message to Kuroka. 'Avoid all the other guys, especially the two school perverts, Matsuda and Motohama.'

'Yes meowster.'

Kuroka took an empty seat behind of Arisu.

Issei had a telepathic conversation with Raynare. 'Raye, they're obviously here because you told them that Kokabiel is dead, but where is that fedora guy?'

'Dohnaseek? He said he doesn't feel comfortable coming to a school since people think he's creepy, which he really isn't but he gets judged by his looks. Instead, he got a part-time job at a nearby delivery station.'

'Oh. Well, at least they can finally live without having to look over their shoulders. You must be happy to have them back, just don't have too much fun without me.'

Raynare giggled. 'Like I could forget about you, dummy~'

"Remember, this Friday is our school cultural festival. Do what you can to contribute to its preparations and make sure to invite your friends and family," Rossweisse announced. "Now, let's go to the school assembly."

. . . . . . .

Hundreds of students filled the school theater, sitting in small yet comfortable chairs.

The school faculty held these assemblies every year at every good school where they talk about all the usual stuff such as getting involved in sports/clubs, dress code for guys and girls, warning girls about sexual assault to prepare them for college, treating teenage boys like animals (which they usually are), bullying, suspendable behavior, behavior worthy of expulsion, etc.

"And now," The Principal said, "We have an announcement to make. As you all know, Kuoh Academy is a very new school that opened only two years ago. Currently, we have a student population of 700, which is pretty good in such a short amount of time and is expected to go up exponentially within a few years, because after the 1st years graduate in three years, the population will be up to 2,000."

Students groaned at the thought.

A/N: I attended a High School, which I graduated from in 2018, that had over 2,000 kids. It was so annoying, I could barely move through the halls at a snail's pace without bumping into someone.

The Principal continued. "Due to the increase in population, we are able to add more diverse classes for students to enroll in. We already have a Band class as well as an Orchestra and Jazz Band, but starting today, students can now enroll into our two newest courses: Rock & Roll, where students can learn to play instruments involved in the genre as well as music assigned to them by their teacher, as well as Boot Camp, which is meant to physically train the 'maggots' who sign up, readying themselves for a possible military future. We already have hired two new teachers for each class, so I would like you to meet them."

Two men walked onto the stage from a room on the side, and Issei's jaw dropped. It is the Doom Slayer and Master Chief.

A/N: Of course, imagine them without armor XD

Neither of them had any of their armor on. They both took a microphone.

The Chief introduced himself first. "I am John. No last name since I grew up an orphan," He lied. "Call me Chief."

'What are the odds that he has the exact same excuse as Raynare's friends?!' Issei thought.

"I am VEGA, an AI who speaks for my Human companion, who is mute," The male synthetic voice announced. "His name is the Doom Slayer. You can call him Slayer-sensei."

The Doom Slayer smirked. 'The name Slayer fits since I am going to slay their innocent ears with some heavy metal, bitches!'

"You may sign up for their classes if you come onto the stage and put your name on one of the pieces of paper for whichever class you want," The Principal spoke.

Some of the girls squealed at how hot the two new teachers are. Rock & Roll class received a very balanced mix of male and female students while Boot Camp class is almost entirely male.

"Motohama, if we join that Rock & Roll class, our chances of getting a girlfriend will skyrocket!"

The bespectacled boy turned to Matsuda. "Or even a harem!"

"Hell yeah!"

They received looks of disgust from every girl. Issei smirked at them condescendingly as if to say, 'Bitch, please. You vermin could never get a girlfriend.'

"Or no. Actually, we'll join boot camp."

Their hopes and dreams shattered in an instant.

. . . . . . .

The Holy Trinity HQ

The Arbiter sighed as he sat all alone, feeling very bored.

. . . . . . .

Kuoh Academy

Lunchtime

Issei was about to head to the Student Council room to play his weekly match of chess with Sona when he was stopped outside the door of the classroom by Kiba.

"Issei, would you please come with me to the Occult Research Club room?"

"... And why would I do that?"

"Rias would like to thank you for saving us."

Issei sighed. "Look, if any of them, especially that self-entitled uppity Princess have anything to say to me, tell them that from now on, they are to come to me directly." He spat out angrily before he smirked at the blond. "Oh, and by the way, I have my own peerage now. It is nearly complete and will only need one more Knight to make a full set. This is happening all while your oh-so-powerful King doesn't even have a Queen anymore. How pathetic she is."

As Issei made his way to the Student Council room, he suddenly heard a loud electric guitar. The sound carried throughout one of the hallways as Issei searched for the origin of the noise. He came upon an all-black door with a red symbol on it that has a skull and the words, 'RIP AND TEAR' written above the skull inside the circle and the words, 'UNTIL IT IS DONE' under the skull.

Issei peaked inside to see the Slayer jamming out to BFG Division. Not wanting to disturb the Slayer, he slowly closed the door.

Issei made it in the Student Council room.

Sona adjusted her glasses. "Issei, we need help with preparing for the cultural festival."

"What do you need?"

"Well, there are many tasks, but for you, I think if you can help us set up a ladder at the front of the main school building and hold it for one of the Student Council members as they climb, that would be great. One of us is going to need to go up the ladder and paint a sign."

Issei nodded. "Sounds good. Let's do it."

Sona smiled. "Thank you. Momo, Reya, and Tsubasa, go with him."

"Yes President."

"Don't worry, Issei. We'll play a match of chess after this is done, although we'll have to be fast about it since lunch will be over halfway over."

As they made their way to the equipment storage shed to acquire a ladder, Issei felt awkward being the center of attention. Momo and Reya were whispering to each other while staring at him from behind and occasionally giggling. Despite having a harem, Issei is still a shy person.

'The more things change, the more they stay the same.' (31) He thought.

Tsubasa giggled at him. "None of us would have ever guessed that any guy could be more popular than Kiba, but you certainly are."

"R-Right. I'm not used to having so many people staring at me, Yura-senpai."

"Tsubasa. Issei, I already told you to call me that, remember? Tsu-Ba-Sa." The blue-haired girl poked his chest three times as she said her name, subtly trying to feel his muscles, admiring them which Issei didn't notice.

"Oh, right. Sorry, Tsubasa." He scratched his hair.

He opened the door to the shed and found a 40 foot tall ladder. Grabbing it with one arm, they made their way to the front of the school. Momo and Reya made their way onto the second floor of the main building and opened the windows.

"Where do you ladies want the ladder?"

"Right in the middle!" Momo shouted so that he could hear her.

He set the ladder where he was instructed and leaned it against the wall above the school entrance, holding it in place as Tsubasa began climbing it, but not before she grabbed one end of a white tarp that was hanging from the window on the right as Momo held onto the material. Now near the top of the ladder, Tsubasa gave Reya, who was in the furthest left window, the other end of the curtain. They taped the tarp to the outside wall.

Reya handed Tsubasa a paintbrush and a bucket of black paint, which she set on the ladder a couple steps above her, careful not to let it fall.

Momo and Reya made their way back outside. Tsubasa painted the words, "Welcome To The Annual Kuoh Academy Cultural Festival" onto the tarp.

As she finished, a sudden violent gust of wind that happened to hit the opposite side of the ladder, right where they didn't want it to. Tsubasa's foot slipped. 35 feet off the ground, she began to fall.

Her eyes widened, panicking. 'Oh crap! Am I going to die here?' She didn't have enough time to do anything but close her eyes and scream for a few short seconds when she felt the embrace of someone's arms. When she opened her eyes, her breath caught in her throat.

It was Issei. He looked at her with a calm look, a small, confident smile. "Are you okay?" His deep husky voice resonated. Standing behind him were Momo and Reya.

Reya's thoughts: 'I'm so jealous!'

Momo's thoughts: 'Issei is so manly!'

Tsubasa thought, 'Oh, this is so embarrassing.'

"I-I'm fine. I thought I was going to die," She stammered, blushing up a storm. He gently set her down, and she looked up at him. "Issei, you just saved my life. How can I ever repay you?"

Issei's face turned red. 'She's so cute!'

"Issei, are you building a peerage?" Momo asked. "If so, maybe Tsubasa could join you."

"Huh?!" Tsubasa and Reya shouted.

"I am. How did you know?"

"Sona inferred that you might be doing so when you first came to her to turn in your form for when you created your club."

"I wouldn't want to steal her away from Sona, so I'll have to ask the President too, but how do you feel about the idea, Tsubasa?"

"I... I would love to join your peerage."

He smiled and nodded. "Great! Let's go talk to the President."

. . . . . . .

As the chess match is about to begin, Issei spoke, "President, I propose a bet."

She looked at him curiously. "Oh? What kind of bet?"

"If I win this match, you have to trade one of the members of your peerage of my choosing to me, obviously not including you or your Queen."

"So you are building a peerage. And if I win?"

"You can have my services in all the remaining preparations for the cultural festival."

She smirked. "Those wagers seem a bit unfair in your favor, but fine. Tell you what, I'm so confident in the fact that you will never win against me that I will even add two more conditions: If you win, not only will I allow you to trade for one of my pieces other than my Queen, but also, you will have a favor from me that I can help you with at any point in the future. The second condition is that if you win, the person you choose from my peerage still stays in the Student Council and cannot join your club for the remainder of the school year."

Issei grinned. "I accept your terms, Lady Sitri," Earning a few giggles from the other girls except Tsubaki, who had her usual stoic expression.

'You're being too reckless and arrogant Sona,' The Vice President thought.

They began playing as everyone watched them with interest, making moves and taking turns every 15 seconds, despite there still being 17 minutes remaining for lunch.

Issei, playing as white, used a very defensive strategy, castling his King with his Rook and placing his King in the corner as Sona began attacking him. Every now and then, he would sacrifice two or three Pawns to ensure that he could kill multiple of Sona's more valuable soldiers, mainly her Knights and Bishops. By the time neutral territories were claimed and set up for battle in the middle of the war, Issei lost four Pawns, two Knights, and one Bishop while claiming all of Sona's Bishops, one Knight, plus a Rook.

In chess, a Pawn is worth 1, a Knight is worth 3, a Bishop is also be worth 3, a Rook is worth 5, and a Queen is worth 9. In terms of individual value of each piece, Issei lost less than Sona.

'Hold my ground, tire the enemy out, and then move in for the killing blow. Like Hitler vs Stalin, which would make me Stalin minus the mass murder.' He thought.

She was getting frustrated and impatient by how unpredictable his moves became. He smirked as Sona made a careless cocky mistake, something she rarely does, by placing her Queen in the line of fire of his own Queen. In the process, he would lose his own Queen, but he decided it was worth it and took out her Queen, making her eyes widen.

She usually plays it safe with her most valuable piece and only goes in for kills that wouldn't put her Queen at risk. Instead, she payed the price for her lack of attention, and it is now his turn to go on the offensive.

Looking up at him, she said, "Have you been practicing?"

He smiled. "Of course I have. I read up on chess strategy, and I found that there are eight specific squares that are essential to winning. As soon as I started experimenting by playing virtually, I really got the hang of it. I'm surprised you haven't figured out my strategy by now."

By now, Issei had two Pawns, a Bishop, and both Rooks. The Rooks are essential to winning in the second half if a player has a very defensive strategy like Issei since they are needed to kill any advancing Pawns trying to promote. He then sacrificed his last Bishop and a Pawn to kill her last Rook with his.

She was trembling. She only had a Knight and five Pawns left, but since none of them were close enough to his base to promote, Issei still has both Rooks and one Pawn promoted to Queen. His rooks waited on both sides of the board in the 3rd row, slaughtering the advancing, desperate Pawns and then forcing a checkmate on her, easily winning in the end, much to everyone's shock.

Sona coughed. "Well, good game. I did not expect you to beat me. So, who do you want from my peerage, and at what price?"

"I want Tsubasa. In exchange, I offer you an alliance between not just both of our peerages, but also on behalf of three specific Dragon gods. Bahamut will be happy to hear this while Ophis and Great Red might not be happy with me speaking on their behalf, but I'm sure they will understand. After all, I am their distant nephew."

Sona's eyes widen. "Oh my god. I had no idea you're related to them! Very well, I accept your terms as long as Tsubasa is fine with this." She turned to the bluenette, receiving a nod. "You will have to give me my Evil Piece back, though. She was my Knight."

Issei pulled out a Rook and showed it to Tsubasa. "Are you ready?"

"I am."

He placed it against her chest, and it turned green, disappearing. Something else reappeared, a Knight Evil Piece. Issei grabbed it and handed it back to the President.

"Pleasure doing business with you."

He exchanged contact information with Tsubasa and left.

Tsubaki leaned forward and whispered in Sona's ear, "I guess that makes him smart enough to be your husband, right?"

Sona blushed much to Saji's annoyance, knowing whatever Tsubaki said has something to do with Issei.

. . . . . . .

Issei's House

A/N: Keep in mind that by now, Issei moved into his new house with his harem

"Alright everyone. This is Tsubasa Yura, a member of the Kuoh Academy Student Council as well as my newest Rook, meaning my peerage is complete."

Tsubasa bowed. "Nice to meet you all. Please take good care of me."

To Be Continued

References:

(28) Breaking Bad Season 5 Episode 6 After Todd did something that would get him killed by inmates in prison. I'm not going to say what exactly due to spoilers.

(29) Kono Suba Season 2 Kazuma's trial arc

(30) JoJo's Bizzare Adventures

(31) Call of Duty: Modern Warfare 2

Issei's Harem (same as peerage members, most to least powerful, will not change):

Issei Hyoudou (Mutated King)

Arisu Yamauchi (OC, Six Mutated Pawn Pieces)

Raynare (Main Girl, Queen)

Akeno Himejima (Knight)

Kuroka Toujou (Bishop)

Irina Shidou (Rook)

Tsubasa Yura (Knight)

Rossweisse (Rook)

Ravel Phenex (Bishop)

Natsuki Murayama (Two Pawns)