Urged by her husband, Makoto, Aoi visits her father-in-law's house alone. There, her father-in-law, Ryōzō, returns home after a three-month tuna fishing trip, having been in a state of abstinence. Mistaken for a housekeeper, Aoi is unable to resist Ryōzō's insatiable desires and is forcibly embraced. Aoi becomes captivated by her father-in-law's wild strength, something her husband lacks, and by his attentiveness as he prepares her freshly caught fish. Taking advantage of Makoto's absence, she sinks into a sea of depravity, and for three months...