stepbrothers

Top row
On the left is Kakuchō: one of the Four Heavenly Kings of the Heavenly Realm and a close ally of Izana. He has noticeable scars and a reserved, serious expression.
In the center is Izana Kurokawa: the former 8th head of the Black Dragon and founder of the Celestial Empire, one of the main antagonists of the Celestial Empire arc. The mask on his face emphasizes his aloofness and desire to keep his distance.
On the right is Ran Haitani: the eldest of the Haitani brothers and also one of the Four Heavenly Kings of the Celestial Empire. He is distinguished by his blond hair, tattoos, and relaxed yet cheeky demeanor.
Middle row:

On the left is Rindo Haitani: Ran's younger brother, also from the Four Heavenly Kings. Recognizable by his braids, earrings, and distinctive grin.
In the center is Takashi Mitsuya: captain of the 2nd squad of Toswa (Tokyo Swastika), one of the gang's founders. Calm and level-headed, yet very dangerous in combat.
On the right is Hajime Kokonoi (aka "Koko"): former treasurer of the Celestial Empire, later affiliated with Bonten. He wears glasses and is known for his cool calculations and business acumen.
Bottom row:

On the left is Seishu Inui: former captain of the 10th generation of the Black Dragon, later affiliated with Toswa. Calm and collected, with a short haircut.
In the center is Haruchiyo Sanzu (formerly Haruchiyo Akashi): known for his loyalty and terrifying character transformations across timelines. His distinctive hairstyle with a bleached streak is his signature look.
On the right is Kanji Mochizuki (or "Mocchi"): another of the Four Heavenly Kings of the Celestial Realm. He's large and imposing, with prominent tattoos and a stern gaze.

Top row:
On the left is Kakuchō: one of the Four Heavenly Kings of the Heavenly Realm and a close ally of Izana. He has noticeable scars and a reserved, serious expression.
In the center is Izana Kurokawa: the former 8th head of the Black Dragon and founder of the Celestial Empire, one of the main antagonists of the Celestial Empire arc. The mask on his face emphasizes his aloofness and desire to keep his distance.
On the right is Ran Haitani: the eldest of the Haitani brothers and also one of the Four Heavenly Kings of the Celestial Empire. He is distinguished by his blond hair, tattoos, and relaxed yet cheeky demeanor.
Middle row:
On the left is Rindo Haitani: Ran's younger brother, also from the Four Heavenly Kings. Recognizable by his braids, earrings, and distinctive grin.
In the center is Takashi Mitsuya: captain of the 2nd squad of Toswa (Tokyo Swastika), one of the gang's founders. Calm and level-headed, yet very dangerous in combat.
On the right is Hajime Kokonoi (aka "Koko"): former treasurer of the Celestial Empire, later affiliated with Bonten. He wears glasses and is known for his cool calculations and business acumen.
Bottom row:
On the left is Seishu Inui: former captain of the 10th generation of the Black Dragon, later affiliated with Toswa. Calm and collected, with a short haircut.
In the center is Haruchiyo Sanzu (formerly Haruchiyo Akashi): known for his loyalty and terrifying character transformations across timelines. His distinctive hairstyle with a bleached streak is his signature look.
On the right is Kanji Mochizuki (or "Mocchi"): another of the Four Heavenly Kings of the Celestial Realm. He's large and imposing, with prominent tattoos and a stern gaze.
All of these characters play important roles in major conflicts between gangs and greatly influence the development of the plot.