Zannen nagara, Haha no Musume wa Soko no Bishoujo de Hanaku Watashi desu!!!

My name is Ada. I was a common child who lived peacefully with my mother and only child. But when I was six years old, my mother went to work, saying, "I'll be back by dinner," and then she disappeared. The landlord of the boarding house arranged for me to live with his daughter, Charlotte, in the downtown area...! What will be the fate of the girls who are caught up in the secrets behind the gorgeous dresses? (Source: Akita Shoten, translated)