Misaki Yosuke is a public prosecutor who passed the bar exam with outstanding results and had a promising future. But one day, he suddenly resigns from his job and sets out to become a pianist. Misaki knocks on the door of a mansion built on quiet, high ground in Kamakura to get lodgings. It is the residence of a prominent local figure and multi-millionaire Katsuki Gentaro, who lives with his housekeeper Tsuzuki Michiko. Although Misaki has the temperament of an artist and his eccentricity is hard to handle, Katsuki quickly recognises Misaki’s talent and personality and decides to welcome him into his house. The Sanadas who live near the Katsukis has been a close family friend from a long time ago. They made a fortune in the furniture business and are as wealthy as the Katsukis. Katsuki’s childhood friend Sanada Kyoko, whom he has secretly loved for many years, is the head of the family. She lives under the same roof with eldest son Tetsuya, a banker; second son Kenzo, who still does not have regular employment at his age and wishes to be a manga artist; Tetsuya’s wife Etsuko; their daughter Haruka, an aspiring pianist; Haruka’s cousin Katagiri Lucia, whose parents died in a disaster; and housekeeper Mikami Kimi, who has served the family for many years. Katsuki asks Misaki to give individual piano lessons to Haruka and Lucia who are just like his granddaughters, but Misaki curtly declines. One night, tragedy strikes the Sanada family. Haruka, Lucia, and Kyoko get caught up in a fire. Haruka is the only one who escapes death despite the large burns she suffered. On the night of the fire, Haruka and Lucia made a final promise. “When you hold a concert someday, Haruka, will you play Debussy’s Clair de Lune for me?” Haruka’s pact with her beloved cousin inspires her to start out as a pianist once again. And Misaki is constantly by her side. Then Kyoko’s will is read and Haruka inherits 600 million yen. A series of queer incidents begin to occur around Haruka...