Oiroke Tantou no Ane to, Higo Yoku Tantou no Imouto ni Hasamereta Watashi

In the kingdom of Famille, there was a viscount named Martinez. This minor noble house, possessing no lands, had three daughters. The second daughter, Fabiola Martinez, has eyes the color of a lamp flame and walnut-brown hair. By herself, she is a lovely young lady. But when all three sisters stand together, Fabiola appears ordinary in comparison. Her elder sister, two years her senior, is an alluring beauty, with a stunning figure. Her eyes are vivid, ruby-like red, her hair straight and glossy black. Her appearance captivates anyone who lays eyes on her. Her younger sister, two years her junior, is a delicate girl who evokes a protective instinct in everyone she meets. Her eyes are a bright, pale pink. Her hair is a soft, wavy, light brown, like the color of faint fragrance. This is the story of the middle child, caught between these two irresistibly captivating sisters, finding her own happiness. (Source: GA Bunko, translated)