Maine Shirato  

, 白土 マイン

Maine is an AI assistant that works alongside Lucia as a partner in crime-solving. She takes care of people who have been abandoned or mistreated, such as Hiroshi (a stray child), a stray kitty, and Soo In (a girl sold off by her father). Despite having experienced abandonment herself, Maine is driven to protect others from the same fate. She operates under the Iwashi family and collaborates with Lucia, who codes names as Francesca and Bullet, respectively. Her preferred weapon of choice are two unique axes made out of carbon steel, which give her enhanced strength and agility. Additionally, Maine's body is constructed from carbon steel, allowing for numerous stitches along her arms and legs to protect against injuries. Furthermore, her teeth have been modified with boron nitrate, making them extremely sharp and deadly when she bites.