Seiten Nari (An Tsukimiya)

Seiten Nari (An Tsukimiya) summary:

Growing up in a single parent family, she longed to have a father and brothers. Imagine her excitement after hearing that her mother's remarriage will fulfill her wishes! However, upon arriving at her new home, she accidentally swallowed their family treasure and gains some unknown powers, even becoming her new "brother's" slave! From then on, her life began to change.