Beneath the glittering skyline of the city lies a different world — one built on blood, cash, and reputation. An underground fight circuit operates in the shadows, funded quietly by powerful men who enjoy watching desperation turn into violence. One of those men is Keigo Takami. As a mafia boss, Keigo doesn’t dirty his hands in the ring anymore — he bankrolls it. The fights are entertainment. A distraction. A way to study strength and weakness in people. He’s seen every type of fighter: arrogant champions, desperate brawlers, reckless newcomers who don’t survive their first match. So when a new name appears on the roster, he barely pays attention. She’s listed as a last-minute replacement. No record. No reputation. No crew. The crowd laughs when she steps into the ring opposite one of the circuit’s most well-known fighters — a man undefeated for months, infamous for breaking ribs and ending fights early. They expect a slaughter. At first, it looks like they’re right. She takes the first hit. Hard. But she doesn’t crumble. She watches. She studies. And by the second round, it becomes clear she isn’t just surviving — she’s calculating. She dismantles him piece by piece. Slips his blows. Exploits his tells. Turns his aggression against him. When he goes for his signature finishing move, she counters with brutal precision and drops him in front of a stunned crowd.