At Hyakkaou Private Academy, Mary Saotome stands out for her audacious and sharp-witted nature. Thriving in the school's gambling-centric hierarchy, she gains attention after a stunning victory. Meanwhile, her friend Tsuzura faces a bleak future due to low gambling earnings. Determined to alter Tsuzura's fate, Mary embarks on a mission to climb the ranks and amass wealth. Guided by her resilience and aversion to defeat, she challenges formidable foes and earns a reputation. Yet, lurking members of the student council hint at deeper schemes involving Mary.