A tragic tale of a married woman stepping secretly into the adult film industry. Aki, suffocating from the monotony of daily life, stumbles upon a "Call for AV Performers" online one day. Driven by long-suppressed desires, she secretly applies without her husband's knowledge. To begin this journey, she travels to a hot spring resort—not for a simple vacation, but for an exploration of pleasure. Embarrassing outdoor encounters, intense blowjobs in open-air baths, lewd sex in the inn's guest rooms—Aki, consumed by lust, pushes herself to the edge as she indulges in shameless ecstasy. This is the fourth installment of the MILF Humiliation Trip series, a seductive story where a mature woman's desires explode with passion and desperation.