Yoru no Yomeiri

After her grandfather's death, 17-year-old Sanjou Yoru becomes the sole heir to the Sanjou manor. Feeling unprepared to manage it alone, she chooses to marry her older childhood friend, Tsukishima Akito, who is ten years her senior. Following their marriage, it becomes apparent that Akito is aware of certain secrets related to the Sanjou estate.