Yukako was cleaning the house, her breasts and voluptuous belly swaying with each movement. Muttering to herself about having gained weight again, she touched her sweaty abdomen. Her son Shinji quietly approached, watching her, then said, "You look healthier than being skinny, and you seem so warm and nice," and began gently touching her belly. At first, Shinji simply caressed her stomach and nuzzled his face against her, acting affectionate, but soon grew aroused, and their relationship took a deeper, intimate turn.