Palette: Shikisai no Shoujo

A boy lives in a world devoid of color. He discovers an old palette in a closet, and when he opens it, a small girl with multicolored eyes emerges. Anything she touches is transformed with color, one object at a time. The boy, captivated by the colors appearing in his otherwise monochrome surroundings, begins to follow her. He wants to see more, telling her, "Show me the color, you just have to do it again."