"Mutation Piece"

The manor's first floor, reception room.

Leo and his party of four arrived in the rather luxurious reception room and took their seats.

A finely crafted coffee table and sofas stood inside the reception room. The interior and decor were lavish, and every piece of furniture was a luxury item. Even the carpet on the floor was obviously expensive. It was perfect for entertaining guests, with no need to worry about making a good impression.

But Leo and Sona Shitori didn't choose to sit there. Instead, they went out to the open-air balcony beside it and sat facing each other at a small white table, making their distance seem less formal.

Tsubaki Shinra pushed a tea cart, taking the place of the familiar, and was preparing tea for Leo and Sona Shitori.

Yukino Yukinoshita stood silently behind Leo, looking every bit like a loyal servant in her master's peerage.

With Tsubaki Shinra attending them, Leo and Sona Shitori chatted like old friends catching up, while returning to the topic they'd just been discussing.

"You mean your Evil Pieces choose their reincarnation targets on their own?"

Sona Shitori sipped her tea and looked at Leo in surprise.

"That's right." Leo held an Evil Piece in his hand, turning it over as he spoke. "When I first tried to make contact with Yukino, the Evil Pieces in my possession reacted in a strange way."

Hearing Leo call her by her first name, Yukino Yukinoshita looked somewhat uncomfortable.

Leo paid no attention to that and continued.

"They seemed to resonate with the reincarnation targets best suited to them. For example, when I made contact with Yukino, the Bishop Piece in my hand kept glowing."

It was an effect the other Evil Pieces hadn't shown.

"Although all the Evil Pieces reacted to Yukino at the time, the Bishop Piece reacted the most strongly. So I think the first change to my Evil Pieces, after they connected with my trait, was that they could give me an indication of who would make a suitable servant, and which kind of servant they were suited to becoming."

Leo brought the Evil Piece in his hand closer to Sona Shitori, and it immediately began to glow red.

"Look, this Piece is reacting to you now. It thinks you're suited to it, and to becoming my servant." Leo joked, "What do you think? Want to consider joining my side?"

"I wouldn't mind." Sona remained expressionless. "As long as you can withstand the wrath of the Sitri Clan and my older sister, I could consider it."

"Then let's not." Leo immediately put away the Piece and surrendered. "The Sitri Clan is one thing, but I don't want your sister with her Sister Complex setting her sights on me."

After all, her older sister was the current Leviathan, one of the strongest Devils in the Underworld. Her strength had even surpassed the strict definition of Maou-Class, reaching a level that would later be called Super Devil Class. His puny self wouldn't be able to withstand her.

"So you chose to give Yukino the Bishop Piece?"

Sona Shitori didn't take the joke seriously and continued asking questions.

"I did consider giving her the Queen Piece. After all, she's the bearer of a Longinus, so she was qualified for it and deserved that level of consideration." Leo glanced at Yukino Yukinoshita, who stood silently behind him. "But after thinking it over, I decided to go along with the Pieces' own choice."

In practical terms, Yukino Yukinoshita really was well suited to the Bishop Piece. That much could be seen from the magical talent she'd displayed after reincarnating.

Her Longinus wasn't a close-combat Sacred Gear, either. It was more suited to long-range, wide-area attacks, so the Rook and Knight Pieces weren't particularly compatible with her. That was also clear from how the Evil Pieces had reacted at the time.

When Leo made contact with Yukino Yukinoshita, all fifteen Pieces in his possession reacted, but the Bishop Piece reacted the most strongly. The Rook, Knight, and Pawn Pieces showed only mild reactions, while the Queen Piece reacted the weakest of all. It was clear that the Queen Piece wasn't particularly suited to Yukino Yukinoshita.

"This is the first change in my Evil Pieces: they react to suitable reincarnation targets with varying degrees of intensity. The stronger the reaction, the more suitable the target should be for reincarnation with that type of Piece."

Leo had reached that conclusion easily, since it hadn't been difficult to guess.

"What about the second change?" Sona Shitori had spotted the obvious implication. "If there's a first change, that means there are others, right?"

"That's right." Leo snapped his fingers and smiled. "The second change is only a theory of mine, but after Yukino successfully reincarnated with a single Bishop Piece, I think it's probably right."

Yukino Yukinoshita and Tsubaki Shinra couldn't understand what he meant, but Sona Shitori grasped it instantly.

"You mean... Mutation Pieces?"

Sona Shitori's eyes gleamed behind her glasses.

"As expected of you. You noticed what I was getting at right away."

Leo smiled and confirmed Sona Shitori's guess.

"What are Mutation Pieces?"

Yukino Yukinoshita knew she shouldn't ask questions in a situation like this, lest she seem ignorant, but she couldn't hold back.

It wasn't Leo or Sona Shitori who explained it to Yukino Yukinoshita, but Tsubaki Shinra.

"Mutation Pieces are a special type of Piece, different from ordinary Evil Pieces. I heard they were an abnormal phenomenon that occurred when the Evil Piece system was established. They appear randomly among manufactured Evil Pieces. Roughly one in every ten High-Class Devils is said to possess one. When a reincarnation target needs multiple Pieces to reincarnate successfully, using just one Mutation Piece is enough to make it work."

Listening to Tsubaki Shinra's explanation, Yukino Yukinoshita gradually understood.

Apparently, the number of Evil Pieces needed to reincarnate a human as a Devil wasn't fixed at one. It depended on the target's abilities and potential. If both were exceptionally high, it sometimes took multiple Pieces of the same type to reincarnate them successfully.

For example, the future Red Dragon Emperor used eight Pawn Pieces when he reincarnated. Their value far exceeded that of a Bishop or Knight Piece, each worth three Pawn Pieces. It also exceeded the value of a Rook Piece, worth five Pawn Pieces, and was second only to the Queen Piece, worth nine Pawn Pieces.

"Yukino is the bearer of a Longinus. Normally, it wouldn't be at all surprising if I had to use both of my Bishop Pieces to reincarnate her. But I only used one. And when I received my Evil Pieces, they'd already been tested. None of them was a Mutation Piece."

Leo spoke at length to Sona Shitori.

"That gives me good reason to believe that, under the influence of my Mutation Trait, all my Evil Pieces might have acquired the same properties as Mutation Pieces. They can use a single Piece to successfully reincarnate a target with high ability and potential as a Devil."

There was no doubt that this was a good thing.

High-Class Devils who were "Kings" often struggled with this question: should they focus on the number of their servants and fill all fifteen slots, or focus on their quality and recruit talented servants even if it meant wasting slots?

If Leo had to face that dilemma, it would be especially troublesome, because both the number and quality of his servants would affect how much feedback and improvement he could gain through his Peerage Transformation trait.

Now, though, he probably wouldn't have to worry about it.

If his Evil Pieces had all gained the same properties as Mutation Pieces because of his Peerage Transformation trait, he wouldn't need to worry that his gains would be diminished by having too few servants. From now on, he only had to consider their potential and recruit as many servants with high ability and potential as possible.

"That's an incredible change." Sona Shitori breathed out in amazement. "All fifteen Pieces being Mutation Pieces? That's unheard of. I can't even imagine how much of an advantage this will give you."

"So far, the changes have only brought benefits. But I still need to explore further to find out whether there are any drawbacks." This time, Leo was especially levelheaded. He didn't gloat and instead spoke calmly. "I've only discovered these two changes so far. I don't know whether there are any others."

"I'll submit a report to Lord Beelzebub. I'm sure he'll be interested." Sona Shitori looked at Leo seriously. "That covers the changes to the Pieces for now. What about the changes in you?"

"According to what you said, your trait should take effect once you've successfully recruited a servant, and give you the corresponding feedback, right?"

"Have you received that feedback yet?"

Under Sona Shitori's intensely focused gaze, as if she wanted to see right through him, Leo smiled slightly.

"Whoosh!"

Three pairs of Devil Wings unfurled behind Leo. At the same time, it was as if flames had erupted around him, and a startling surge of Demonic Power burst forth.

"That's...?!"

Sona Shitori's eyes narrowed.

"Six wings?" Tsubaki Shinra was even more shocked, staring in disbelief. "And that Demonic Power..."

That Demonic Power was already stronger than her master's, Sona Shitori's.

How could this be?

Tsubaki Shinra clearly remembered that Leo had only recently advanced to High-Class Devil. His Demonic Power had been considerably weaker than her master's.

Yet now, not only did he possess more Demonic Power than her master, but his standing as a Devil had risen as well?

"This is what I gained this time." Leo withdrew his Demonic Power and folded his wings away. "What do you think? Not bad, right?"

As for Zenith Tempest, Leo didn't mention it.

It wasn't that he didn't want to tell them, but that he felt it was too soon.

It was the second-ranked Top-tier Longinus among all the Longinus. If he revealed it, the entire world of Devils would be thrown into an uproar.

Leo still wasn't familiar with how to use Zenith Tempest. He thought it would be better to keep a low profile for now and reveal it once he was strong enough.