manga key panel, library by a large window on an overcast day, soft diffuse light, character reading a letter with hands clearly shown, face in three-quarter view with restrained emotion, background shelves simplified into tonal blocks, a few purposeful props (bookmark, pencil, stamped envelope with no readable text), clear eye path from letter → face → window, clean lineart, delicate line weight on facial planes, restrained screentone shading for depth, cinematic composition, quiet character-first drama