Tsubaki-Iro No Prigione

As the heir to a grand estate, Saionji initially shows no interest in claiming his inheritance upon his father's passing. However, an intriguing opportunity presents itself when Sannomiya Rei, a captivating secretary, persuades him otherwise. Reluctantly, he sets foot in his ancestral home – a magnificent mansion teeming with devoted maids who, it dawns on him, may have served his late father in more than just domestic duties...