"I was reborn as a greedy younger sister and was trying to steal my older sister's fiancé, but this is just too much even for me."

Kimura Ayuri, an ordinary office worker, realizes that she has been reincarnated as a character in an otherworld manga. She has been reincarnated as Ashley, a girl who has always coveted everything her older sister owns. Since childhood, she has stolen her sister's dresses, her necklaces, and has even been trying to steal her sister's fiancé. However, Ayuri is puzzled. This fiancé named Warren isn't attractive at all, is he? Why would Ashley desire such a man? While wondering about this, Ayuri discovers a diary written by Ashley...