In the height of summer, one man and three sisters serve at a suburban mansion. The eldest sister, calm and composed, works as a housekeeper; the second sister, intelligent and reserved, is a secretary at a foreign company; and the youngest sister, free-spirited, works as a cabin attendant. With the master’s permission, the eldest sister invites her younger sisters to the mansion during Golden Week. Though the three rejoice in their reunion, the man’s abnormal desires soon begin to quietly erode their everyday lives— A tale of one summer’s transgression, where pleasure, control, and bonds intertwine.