[Machine Translation] You only live once. Then, the one who enjoys it the most wins! Marianne, an incredibly positive girl genius, brings happiness to everyone with her unconventional ideas! Marianne, the second daughter of Count Landfuria, is a genius girl who loves books. Her current problem is that her half-sister shuns her. ( Is it the fate of the second daughter?) However, Marianne gradually melts her sister's stubborn heart with her natural cheerfulness. Furthermore, the second prince she meets at the school takes an interest in her positive attitude toward life...? The story of the reform of the domain by the daughter of the sun, who brightens the world around her with her abundant talents and powerful energy, is about to begin!