After being filled in by Sona, Yukio learns about the world beyond simple mortals like himself.

Sona proceeded to explain to Yukio what the demons were and how the peerages and Evil Pieces worked. Needless to say, the boy was impressed to learn of the existance of this mythical creatures, but as he listened, he let his guard down for one crucial question.

"Your flute, is it a Sacred Gear?" -

"Sacred Gear? Is that what my flute is called?" -

"Please, tell me what you know about it" -

"Well... It was a gift from my grandmother, she told me its name was 'Trickster's Fantasy" and that it was important, as it had something of great value inside. Whenever I play it..." -

"When you play it? Can you show it here?" -

Yukio, despite being nervous, obeyed. As he was playing the flute, Sona and Tsubaki noticed how he changed. Now, his Kuoh uniform had turned into what seemed to be a light armor that combined white and purple, with the symbol of a dragon painted in gold in his chest. His left hand turned into a claw while the right one remained normal, and one of his eyes had changed into that one of a reptile.

"Whatever this is... It happens every time I touch the flute, I don't know what is it and I'm too scared to tell my parents" - Yukio said while he stopped playing - "At least I can return to normal when I want to" - in an instant, the armor dissapeared and his hand and eye returned to normal.

Sona simply smiled at the sight of Yukio. At last, she had found a piece that could give her the power she'd need to match Rias' Pawn.

"Tell me, are you perhaps interested in joining me and my peerage? We'll teach you how to control your powers and manipulate your flute and its powers. It's, at the end of the day, a win-win, what do you say?" -

The promise was indeed tempting for the boy. While he couldn't know if Sona was telling the truth, he had his power in case she tried to betray him.

"Alright, I'll join you" -

"I'm glad you made the logical choice. Now let us begin" -

With those words, Sona started the process to reincarnate Yukio into one of her Pieces. She originally planned to use 1 Pawn, but this proved impossible, he needed more. With that, Sona decided to break out her Mutation Piece, allowing her to turn Yukio into her first Pawn.

"Congratulations for joining the Sitri Peerage" - Tsubaki said, without changing her regular stern looks.

"Very good, I hope you enjoy your time with us. Now, you may return to class" -

As Yukio was about to retire, Sona caught his attention once more - "Oh, and be aware that now you have oficially become a member of the Student Council. I'll have Tsubaki tell you all about our work during your break time" -

As he was heading back to his classroom, he noticed that someone was looking directly at him, a woman with long black hair and a voluptuous figure.

"Can I... Help you?" -

"You're one of the new students right? You seem to be close to Sona, even if you just arrived. Are you sure there's no funny business going on?" -

"Wh-What are you talking about?" -

"Fufufu, don't worry, it's nothing" -

Yukio simply took off as fast as he could, leaving that woman behind, who simply stared down at him.

"Ara ara, this surely is interesting, I wonder how Rias shall react" -

After Yukio returned to his classroom, Sona and Tsubaki stayed together for a while longer in their room. Recently, there was an attack from Fallen Angels that led to Rias gaining a new Pawn and a Bishop, so they were questiong if there might be more in Kuoh in hiding. However, their conversation was cut short with a beautiful woman with long red hair entered the room, Rias Gremory.

/A few hours after/

Yukio was now on his break. Sitting alone under a tree, the boy was eating a meal his mom packed for him. Everything seemed calmed until Tsubaki decided to approach, as they needed his presence.

Following Sona's Queen to the Student Council Room, they entered, being met by not only Sona and Rias, but the same woman that Yukio saw spying on him.

"So, he's your new Pawn? Impressive Sona" - Rias said.

"Thanks, but enough compliments, you need our help right?" -

"I do. You're Yukio right? My name is Rias Gremory, I'm the heiress to the Gremory Clan and Sona's friend" -

"Nice to meet you Rias" - Yukio extended his hand to greet her, which she gladly took.

"Now that you two know each other, Rias..." -

"Right. I'm in a situation right now, I need to defeat a devil called Riser Phenex to avoid having to marry him, and I came here to ask Sona to help us train as we have 10 days to prepare" -

"As such, Tsubaki, you and myself will join them in their training. This will also help you get a better understanding on how Trickster's Fantasy works. I must say, I wanted to keep Yukio as a surprise, but the situation at hand calls for him to help us" -

"It would be an ho-An honor to help Sona's friends train" - Yukio said, hesitating halfway through due to his nervousness.

"Thanks for your help Sona, it's greatly appreciated" - Rias said while bowing.

"No problem. Yukio, prepare your stuff, we leave tomorrow" -

"Tomorrow!?" - while he boy was going to protest, a single look from Sona stopped him - "Understood..." -

Before we end the chapter, I just wanted to make a quick announcment, since I got yesterday 2 reviews covering the same topic:

While Yukio steal all of Issei's harem? No. However, he will have 1 girl from there which identity shall remain a secret for the moment. He also won't have a harem since those are too hard for me to write, 3 girls at most.