Prelude

Issei soon found himself in some part of the underworld alongside Grayfia.

"If you would follow me Issei-sama, then I will guide you to the Sirzechs-sama and the others" she bowed towards him making Issei sigh as he was not used to all these formalities.

"Alright. By the way, you do not need to address me with the -sama. I'm a dragon and we have no need for formalities. I would much prefer if you would address as simply Issei if that's alright with you" he stated. Grayfia nodded.

"Very well then, Issei-san it is then. In that case, feel free to call me Grayfia or Lucifuge-san as you have been doing. Both are acceptable." She responded making Issei smile.

"Great, in that case, please lead the way Grayfia-san" he motioned her to lead to which she nodded and he followed behind her. As he followed, he looked at his surroundings and was amazed that the underworld almost looked like the human world except with all the devils flying around. In a way, it makes sense. Most of the devils interaction lie in making contracts with humans so they must have incorporated much of the human's way of living into their own. Pretty cool if you asked him. He then took a look at the silver haired maid in front of him. He had to admit that she was breath-takingly beautiful and possessed a level of grace and maturity that most people nowadays do not have. He suddenly started to imagine both of his mates greeting him in a maid outfit and calling him Master. It took all his will not to have an instant nosebleed at the thought of it. He quickly shook his head and decided to start some idle chat with Grayfia to help clear his mind as they made their way to their destination.

"Um, Grayfia-san, if you don't mind me asking. Are you married to the Maou Lucifer, Sirzechs? I have heard Rias refer to as you One-sama which would imply that you married into the family." He was very curious about that, yet it would seem that a small part of him dreaded the answer to the question. To his silent relief, however, she shook her head.

"I'm not married to Sirzechs-sama. We used to be involved with each other a long time ago but we separated when we realized it wasn't going to work between us. He is what the humans would refer to as my ex-boyfriend. As for Rias Ojou-sama, even after we broke up, she still continued to call me her one-sama which Sirzechs and I didn't mind although only in private" She explained which surprised him.

"Oh I see. However, doesn't it feel weird working for him as his Queen?" he asked.

"Not really. Sirzechs-sama and the Gremory still treat me as a member of the family and I am honored to work for them both as a maid and as Sirzechs-sama queen." She stated still looking forward.

"Wow, you really are an amazing woman" he spoke honestly, from his heart. For a moment, he though he saw her faltered in her steps.

"Everything alright, Grayfia-san?" he asked worried he might have made her lose focus by accident and almost made her slip.

"Everything is alright Issei-san. We are almost at our destination." She answered seemingly alright. What Issei didn't know and wasn't able to see since her back was turned was the slight blush she had when he complimented her as well as a small smile. How long has it been since someone earnestly complimented her without trying to suck up to her or woo her. Luckily, she was able to quickly regain her focus so that Issei didn't notice.

Eventually, they made it towards the building where the Maous are located to spectate the game. Gremory and Phenex family will be watching it in a different location. They could have watched it all in the same room but Sirzechs still held a bit of malice towards the two families for forcing his beloved younger sister into this situation despite the fact that she was supposed to be given until the time she started university before her unwilling marriage to Riser took place.

Grayfia knocked twice.

Knock Knock

"Who is it?" Grayfia recognized Sirzechs voice coming from behind the door.

"It's me Sirzechs-sama. I have brought Issei Hyoudou as you've requested." Grayfia answered.

"Oh, please come in." he responded in a friendly manner once he heard it was Grayfia.

She then opened the door as both of them entered. Issei surveyed the room and spotted 3 figures in front of him. The first was a crimson haired man with blue eyes who looked to be in his 20's. There was no doubt that he was Maou Lucifer Sirzechs Gremory, Rias brother. In fact, he looks like a male version of Rias so there was no way to mistake who he was.

Next to him was a cheerful twin hailed woman who had a gorgeous figure despite her child sized body. He assumed that this was Serafall Leviathan. The only reason Issei wasn't sure was due to her outfit. While the other two were wearing formal clothes befitting their status as Maou, she was wearing what seemed to be a Magical girl uniform. She did look familiar. Where the heck had he seen her?

By process of elimination, that would mean that the last man in the room was Ajuka Beelzebub. He had heard quite a bit about him from Tannin and Tiamat. So… this was the man that created the Evil piece system which saved the devils society from extinction. Based on his expression, he looked like he didn't really want to be here. Tiamat did tell him that Ajuka didn't care much about his responsibilities as a Maou and spent the majority of his time in his lab, creating things. In a way, he kind of resembled his dad in the way that he was uninterested in others affairs and simply wanted to fly in the Dimensional Gap freely.

One thing he noticed instantly was the fact that the three of them were very strong. Particularly, Sirzechs and Ajuka. They would make for very tough opponents. Part of him would have loved to fight them. It is in a dragon's nature to want to fight strong opponents and Issei is no different. From what he could sense, they were definitely the strongest people, aside from his parents, he has met so far. It made sense why his sensei tannin said he would lose to the crimson haired Maou. Rias has a long way to go if she ever hopes to catch up to her brother.

The aforementioned man, upon seeing him adorned a smile and made his way to greet them. He was surprised a bit upon glancing at Grayfia. Despite looking the same as always, he couldn't help but notice that she seemed to have a suppressed smile on her face and he had a feeling that it was due to the person next to her.

'interesting' he thought but for now he would leave that for later.

"Greetings, you must be Issei Hyoudou. My name is Sirzechs Lucifer, one of the 4 Maous of the Underworld, it is a pleasure to make your acquaintance" he introduced himself in a friendly manner as he held out his hand.

Issei shook it.

"It's a pleasure to meet you as well. I've heard a lot about you from Tannin-shishou. As you stated my name is Issei Hyoudou."

"Oh, so you are acquainted with Tannin-dono?" Sirzechs was surprised to hear that Issei had some relation to Tannin. Although it did alleviate some concern since it must mean he belongs to Tannin's faction.

"Yes, he is my sensei and has trained me for many years." He explained. Tannin had once told him that should he be introduced to the maou to state that he was with him. It would help mitigate any worries towards him. It was a lot better than revealing his secret. It seems he was right given the maou's expression.

"I would like to thank you for inviting me to see Rias rating game."

"It's only natural. I heard from Grayfia that you and Tiamat had helped train them during the 10 days they had been given. I do thank you for that." Sirzechs thanked Issei for helping his little sister and her team train. They needed all the help they could get to win against Riser.

"You're welcome but it is only natural to help one's friends" Issei smiled. His answer seemed to alleviate Sirzechs worries about the boy. From what he heard from Grayfia and from what he could sense, there is no doubt in his mind that Issei is a dragon and a powerful one at that. The fact that he showed absolutely no fear in the face of 3 Maous, 2 of which are super devils only enforced his thoughts. Therefore, when he had heard that an unknown dragon was located in his sister's territory, he couldn't help but worry over here well being. The same goes for his wife. Thankfully, it would seem his worries were ill-founded. Added to the fact that he seems to belong to Tannin's faction, dragons are honest creatures so the fact that he referred to Rias and her peerage as friends alleviated all his troubled thoughts.

"Oh Sirzechs-chan, is this him?" Issei saw Serafall approach them.

Sirzechs nodded his head.

"Indeed it is. Let me introduce you. This is Serafall Leviathan. She is in charge of Foreign affairs in the Underworld and she is also my wife. Serafall, this is Issei Hyoudou" He introduced his fellow maou and wife to Issei.

"Just like Sirzechs-chan said, I'm Serafall Leviathan or Magical girl Levia-tan. Pleased to meet you" she made her pose just as she did in her show. She was certainly a very cheerful individual Issei remarked. It then clicked in his head where he saw her when she introduced herself.

"Oh, so you're from that Magical girl show?" remarked Issei. This instantly caught Serafall attention as she was instantly all over him which caught him by surprise.

"Yes Yes so you've seen my show? Are you a fan? I'm always so happy to meet any of my fans." She had stars coming out of her eyes illustrating how excited she was to know that Issei watched her show.

Issei was taken completely by surprise by her behaviour considering that she is supposed to be a Maou.

"um… I wouldn't say I am a fan but I used to watch part your show in the past with my mother and friends." Issei stated. It's not like Ophis loved the show or anything, but she did it mostly to annoy great-red since he clearly did not like it. Therefore, from time to time they would watch the show and even though he didn't really like it, Akeno seemed to enjoy it so he watched it with her. Does she still watch it? He never asked. Of course, it's been over 10 years since he had last seen the show due to the fact that he was focused on his training. It was why he didn't immediately recognize Serafall until just now after she introduced herself.

"It's a pleasure to meet you too. Hope we can get along." Issei said. Serafall nodded before he turned towards the last member of the group.

"This is Ajuka Beelzebub, our chief advisor of our technological department as well as a very good friend of mine" Sirzechs introduced the final Maou in the room to Issei. Of course, Issei already knew who Ajuka was thanks to Tiamat and Rias. They both gave him a general understanding of who he was, albeit completely different. Rias talked about how Ajuka was an extremely smart individual and that it was thanks to him creating the evil pieces that saved their species from becoming extinct. Tiamat, on the other hand, basically described him as an obsessive addict that loves to create things which made him laugh. They both also mentioned that Ajuka was an extremely powerful devil rivaling Sirzechs. Both of them were known as Super Devils and were known as the strongest devils in existence, including one other.

"Greetings" Ajuka gave Issei a brief welcome with a small bow of the head which Issei returned.

"So you are Ajuka Beelzebub, I have heard quite a bit of you from Tiamat-chan." Issei said finally getting to meet the man he heard quite a bit about. This caught Ajuka's intrigue.

"Oh and what is your relation to her, may I ask?"

"She is my mate" Issei's answer caught Ajuka completely by surprise. He is very well acquainted with Tiamat and knew part of her history involving Ddraig. Although, it ended badly, it showed that Tiamat would only mate with someone stronger than her. Typical behaviour of a female dragon. However, Tiamat was the strongest dragon king, capable of standing toe to toe with Maou class beings and if she mated with the boy in front of him, it meant she acknowledged that he was stronger than her. 'How very interesting' was Ajuka's current thoughts. His eyes showed a keen interest in the being in front of him. Seeing this, Issei felt a small shiver as if he was being analysed.

Seeing this, Sirzechs intervened.

"Ajuka, can't you see you are making him feel uncomfortable. Issei is here to see the rating between Rias and Riser, not to become part of an experiment" Sirzechs knew what the glint in his friends eyes signified. It was just one part of Ajuka. Whenever he becomes fascinated with something, he wants to understand it.

"Your no fun" remarked Ajuka as he backed off from the boy.

"Sirzechs-sama, Ajuka-sama, Serafall-sama and Issei-sama, it is almost time for the match to begin." Grayfia interrupted their conversation, letting them know that the fight was about to start and they should take their seats. Everyone nodded and Issei ended up sitting between Sirzechs and Grayfia.

Before the game begins, Sirzechs asked Issei a question.

"What are Rias odds at winning the game?" He wished to know what his sister's chances were after her training.

"To be honest, her odds aren't that great. As you probably already know, her opponent is the worst match up for her. Rias power of destruction is a dangerous ability but against Riser phenix regeneration, her ability is rendered useless. Despite all our training, she is not yet at a level where she could defeat his regeneration in a single blow." He begun explaining. Sirzechs could only nod since he also understood where he was coming.

"However, that does not mean that they are helpless. Their odds may be slim but they do have a chance at winning. Rather, I have faith that they will overcome the odds and come out of this match victorious. They have trained extremely hard and have become so much stronger. We have already come up with a plan in order to deal with her opponent. All that is left to do is to see if they can accomplish it." Issei finished explaining.

Sirzechs nodded. "I see! I am very happy to hear that." He could only hope that Issei was right and that his little Ria-tan would be able to come out of this fight victorious otherwise she would be forced to marry with Riser Phenix and there is nothing he would be able to do to intervene due to his status as a Maou.

"The game is about to begin. If both teams are ready, then please head to the magical circle that should have appeared before both teams"

They heard Grayfia announce the start of the Rating game. Ajuka snapped his fingers and conjured multiple screens that showed both teams.

And so the game has officially begun.