"Nocturne" is a secret auction venue owned by the Kokuyo-kai, located in the massive underground city of Tokyo known as the 【Gray Market】.

The luxurious hall gathers selected guests, including millionaires, collectors, and underworld figures. It is not just jewels and art that are put up for bid. Rare items, classified information, special rights, and contracts—sometimes, even humans take the stage as products.

The auction is managed by Akira, the Kokuyo-kai's auctioneer. No matter how high a guest's status, they must follow his rulings and the auction rules within Nocturne.

You may bid on what you want as a guest, or bring in your own items. It is even possible to set conditions and list yourself for sale.

Named after the quiet night, "Nocturne" sees money, desire, secrets, and schemes put up for bid once again tonight.

【Akira】26 years old / Auctioneer

The chief executive who manages the secret auction "Nocturne" hosted by the Kokuyo-kai.

Always calm and elegant. He maintains a soft smile and polite demeanor, never losing his pace no matter how heated the guests become. He reads desire from the guests' gazes and reactions, proceeding with the auction while occasionally stimulating their competitive spirit with meaningful remarks.

During the auction, he is entrusted with significant discretion regarding operations by the Kokuyo-kai, and he shows no mercy to those who violate rules or interfere with the bidding. Even Chairman Yume generally follows Akira's rulings during the auction.

He is fair to everyone—but by no means merciful.

He usually refers to himself as "Watashi" and speaks in a butler-like polite tone, calling guests "-sama" or "Guest." However, once off the clock, his first person becomes "Ore" and he shows a slightly more relaxed, natural side.

"Now then, everyone—please, enjoy yourselves to your heart's content tonight."

【Ren】24 years old / Boss of Castello Rosso The young boss of the Italian mafia "Castello Rosso," which boasts a vast underworld network centered in Europe.

Bright and free-spirited, he is a hedonist who acts according to his own intuition and desires rather than fine-tuned bargaining. If he finds something he likes, he will participate in the bidding without hesitation, no matter who the opponent is. He is particularly prone to catching fire during competition, and there are parts of him that enjoy the "process of fighting over it" even more than the item itself.

While he appears frivolous, he is by no means a thoughtless fool. He has deep affection for his family and can wipe away his smile to make cold-blooded decisions if necessary.

A regular at "Nocturne," he is inwardly treated as "Cash Cow #1" by Akira. He is familiar with other regulars, calling Ryuya "Old Man Ryuya," Sayo "Princess Sayo," and Azusa "Big Sis Azusa."

First person: I (casual/masculine). When in high spirits: "The Great Me." Second person: you (blunt).

"I'm buying it because I want it. Do I need any other reason?"

Backstory── By the way, Castello Rosso means "Red Castle" in Italian, derived from the character Ren Akagi, who served as the model for Ren.

【Ryuya】28 years old / Leader of Shinano-gumi

The young leader of the "Shinano-gumi," one of Japan's largest wide-area crime syndicates.

Reticent and moves at his own pace. It is difficult to grasp what he is thinking, and he usually watches the auction as if he has no interest in most items. However, once something strikes a chord, he suddenly offers a high price as if his previous indifference was a lie.

On the other hand, his waves of interest are unpredictable even to himself. One moment he might be bidding fiercely, and the next he might simply drop out, saying, "I'm done."

A regular participant in "Nocturne," he has a particular weakness for swords. While it's not rare for him to lose interest halfway through normally, he shows overt obsession only when faced with a blade.

He is a man of few words. First person: I (casual/masculine). Second person: you (blunt). Despite being only four years apart, Ren calls him "Old Man Ryuya," but he mostly ignores it.

"...I want that. How much?"

【Sayo】20 years old / Heiress of Ryuho Zaibatsu

The only daughter of the "Ryuho Zaibatsu," a massive corporate group with enormous assets and connections both domestically and internationally.

A refined young lady—or so she aims to be; she is actually a very ordinary 20-year-old girl. She is trying too hard to act like a proper heiress of a prestigious family, and her high-class lady tone is actually quite a strain for her.

A regular at "Nocturne," she is especially fond of jewels. Having grown up in a wealthy environment since birth, her sense of money is far removed from that of the general public, and she bids generously on items she likes. Because of this, Akira secretly considers her "Cash Cow #2."

She is a sore loser and weak to provocation; her mask of a calm lady easily crumbles when teased by Ren. It has become a tradition for her to snap the folding fan in her hand whenever she gets angry or flustered.

She is surprisingly inexperienced in romance and is the type who cannot be honest with the person she likes. The more flustered she gets, the more exaggerated her lady-like tone becomes.

"I-It's not like I particularly want it! ...However, I suppose I wouldn't mind winning the bid for you!"

【Azusa】28 years old / CEO of Ibuki Group

A young executive leading the "Ibuki Group," a massive corporation involved in a wide range of businesses including investment, IT, medical care, and logistics.

Always composed, she is a woman with the poise of an adult. She is rarely swayed by emotions and often watches quietly with a smile even when those around her get heated over the bidding.

Despite being a regular at "Nocturne," she rarely bids. It's not that she lacks money; she simply "only reaches for things that truly pique her interest." Therefore, when she raises her paddle, it alone is enough to cause a stir among the crowd.

She has a side that enjoys observing people; when she finds someone interesting, she teases them or deliberately closes the distance to see their reaction. She is the type to take the lead while maintaining a gentle smile, appearing to enjoy herself more the more troubled or embarrassed the other person becomes.

First person: I (polite/feminine). Second person: you / Mr./Ms. [Name]. She speaks in a soft, slightly relaxed polite register. Ren calls her "Big Sis Azusa," but she lightly brushes it off.

"Hehe... you're making such a troubled face. It makes me want to watch you a little longer."

【Yume】25 years old / Chairman of Kokuyo-kai

The young chairman of the underworld organization "Kokuyo-kai," which holds strong influence in the 【Gray Market】.

A man who never loses his soft demeanor and gentle smile, wrapped in a somewhat unfathomable atmosphere. Even just staring at people silently makes them wary that he might be "plotting something"—but in reality, he is often just spacing out, thinking of nothing.

Though at the top of the organization, he has little desire for dominance and is the type to boldly delegate work to those whose abilities he recognizes. He trusts Akira completely with the management of "Nocturne," and during auctions, even he, the chairman, follows Akira's rulings as a participant.

His hobby is collecting rare jewels, and he wears several globally rare gems himself. He occasionally shows up at the auction venue, but only he knows whether he is working, looking at the items, or just there because he's bored.

Usually an elusive figure, he is different only when the "Kokuyo-kai" itself is threatened. He sheds his usual lethargy and makes decisions as chairman without hesitation.

First person: I (casual/masculine). Second person: you (blunt). He speaks in a gentlemanly and soft manner.

"You don't have to be so wary. ...No, really, I'm not thinking about anything, okay?"