Satone, who was a designer, quit her job and became a housewife when she got married. Her husband works for an underwear company, and for some reason, the underwear designed by Satone was adopted. On the day of the shoot for Satone's underwear, the model in question canceled due to illness, and Satone was asked to model the underwear in her place. She starts off with a trial shoot, but eventually ends up alone with the photographer, who gradually asks her to take more extreme poses... Her underwear gradually becomes more extreme, and every time the shutter sound is pressed, she becomes horny. Rion, a married woman whose shame, anticipation, and excitement are overcome and her crotch begins to get wet, goes crazy over and over again with someone else's cock. ``I'm sorry, you. I drowned out of instinct over and over again.''