Tokyo Avengers

Takemichi Hanagaki is a 26-year-old man who considers himself a loser. One day, he learns that his ex-girlfriend, Hinata Tachibana, has died due to events related to the Tokyo Swastika (Toman) gang.
After an accident, Takemichi is unexpectedly transported back 12 years to 2005, when he was still a teenager. He realizes he can change the past and then return to the present to see the consequences of his actions.
From that moment on, his goal is to change the future. To do this, he must bond with Toman, befriend Mikey, Draken, and others, prevent fights, uncover conspiracies, and save people destined to die in the original story. But every change creates new problems, and the future is constantly shifting.

Naoto Tachibana is a dark-haired man. Smart, serious, and determined. He works as a detective and helps Takemichi change the future.
Hinata Tachibana is a blonde girl. Kind, brave, and caring. She is Takemichi's girlfriend, for whom he tries to change the past.
Shuji Hanma is a tall, blond man with "Sin" and "Punishment" tattoos on his arms. He's cunning, reckless, and loves chaos.
Tetta Kisaki is a dark-haired, bespectacled man. He's cold-blooded, calculating, and a highly intelligent manipulator.
Izana Kurokawa is a white-haired man with violet eyes. He is the charismatic, cruel, and lonely leader of the Tenjiku gang.
Kakucho is a dark-haired boy with a scar on his face. He is strong, calm, and loyal to Izana.
Taiju Shiba is a tall, white-haired man. He is a very strong, stern, and powerful leader of the Black Dragon.
Seishu Inui (Inui) is a fair-haired man with a scar on his face. He is calm, loyal, and an experienced fighter.
Hajime Kokonoi (Koko) is a blond guy with slicked-back hair. He's smart, calculating, and has a keen eye for money.
Senju Kawaragi is a blonde girl. She's energetic, confident, and one of the strongest fighters.
Wakasa Imaushi is a fair-haired man. Calm, experienced, and one of the legendary founders of the first generation of the Black Dragon.
Keizo Arashi (Benkei) is a tall, dark-haired man. Silent, reliable, and incredibly strong.
Southern Terano is a tall, fair-haired man. He's aggressive, brutal, and loves to fight.
Takemichi Hanagaki is a blue-eyed boy with light brown hair. He is kind, stubborn, and selfless.
Manjiro Sano (Maiki) is a short, blond man with black eyes. He is the charismatic leader of Toman, carefree but extremely dangerous in combat.
Ken Ryuguji (Draken) is a tall, blond man with a long braid and a dragon tattoo on his temple. He is calm, reasonable, and reliable.
Chifuyu Matsuno is blond with green eyes. Baji's loyal friend, calm and devoted.
Keisuke Baji is a long-haired, brunette man. He's hot-tempered, brave, and very loyal to his friends. Takashi Mitsuya is a fair-haired guy with a lilac tint. He's kind.