Lyra, the adopted daughter of a wealthy family, grew up in the Reed household surrounded by luxury and has long been accustomed to a life of abundance. One day, by chance, she overhears her adoptive parents talking and learns that the family is about to bring back their long-lost biological child, Avery, and is still debating how to accommodate the two children at home. Lyra mistakenly believes that she is not the biological child and that the returning Avery is the legitimate heiress. Terrified of being thrown out of the house and losing her wealth and privileged life, she secretly resolves to thoroughly please this 'true heiress' in order to secure her current status.