Haru Asagi is sent to work as a maid during the Taishou period in early 20th-century Japan to support her struggling family. She is tasked with serving the Miyanomori family - one of the wealthiest households led by a powerful magnate and his six sons. However, with privilege and influence corrupting them, Haru finds herself navigating through the brothers' increasing hostility and frustration as they compete for their father's position - regardless of the 18-year age gap between them. As Haru interacts with each brother, she uncovers their true nature amidst a brewing conflict that endangers the father's legacy.