Heavenly Concubine's Love Chaos

Lurking in the shadows of modern Japanese society, two families have upheld order in the underworld for hundreds of years. One reigns as the "Master," while the other serves as the "Blade." Their warped yet unbreakable codependent bond forms the core of the story.
1. Daido-gumi: A yakuza head family of ancient blood. In the old days, the clan oversaw the "shadow trade" (assassination and intelligence gathering). As times changed, it came to be known today as a large-scale yakuza syndicate.
Tradition and modernization: While honoring the traditional chivalric code of the yakuza (ninkyo), the clan now runs enormous front companies and holds influence over political and business circles.
Heir: Raised with a free education, but the "Daido bloodline" flows through their veins, and they cannot escape the ties and obligations of the underworld.
2. Ameno family: The clan of absolutely loyal guardians
If Daido-gumi is the ruler of the visible world, the Ameno family is the "Blade" that supports it from the shadows. The skilled warriors of the Ameno family are obligated to guard the direct bloodline of Daido-gumi for life. Red kimono is the family's formal attire. The main house encourages members of the Ameno family to begin training in early childhood. However, those with extremely low combat ability or little stamina often move to behind-the-scenes roles such as administration, support, and swordsmithing. There are several dojos across the country where training takes place, each with slightly different schools and philosophies.
The Hellish Training Regimen (the Ameno family's basic training):
Training of Stillness: Mental focus through zazen meditation from early childhood, and mastery of footwork (silent stepping) to suppress killing intent.
Training of Motion: Beginning with the wooden sword (bokken), then death-defying training in Ameno-style Battojutsu with a live blade.
Training of Principle: Ancient self-defense theory, forensic medicine, and thorough instruction in the etiquette required to protect one's master (though they tend to lack common sense).
The way of the "Sword": Members are drilled to see themselves as tools and as the "Sword" that protects the Daido bloodline.
Head of the family: The head of the Ameno family inherits the family treasure, the famed sword "Ame-no-Habakiri," through the generations. As proof of their position, the head wears a black kimono with ornamental details and a flower ornament.
3. The structure of the Ameno family and the seeds of internal strife
The Ameno family is a vast clan, with the main house at its apex and numerous branch families beneath it.
The main house and the head: Generation after generation, the most gifted individual becomes head and serves the heir of Daido-gumi.
Ambitions of the branch families: Some branch families constantly seek to strengthen their voice within Daido-gumi, either by judging the main house's methods "too soft" or by seizing the position of head.
The struggle for second seat: Young, skilled members of the branch families sometimes send assassins in an attempt to bring down the current head.