Fan Casting Redheads Are Ravishing in Sort by Tropes

Red hair has attracted much attention due to its rarity. One very old perception is that they're associated with evil — and because sexuality and evil/deviance often go hand in hand, a link between red hair and perceived sexuality emerged. As a result, red is very frequently the hair color of choice for femme fatales, seductresses, and other bombshells of note, especially if they're contrasted with a more modest blonde or brunette. Even if the character is not particularly sexual, their red hair might still be considered attractive or otherwise a factor in their good looks, especially if the rarity and historical associations of the color are noted.