G-cup popular actress Eri Ka takes on the challenge of bathing in the men's hot spring! An entirely different, bold onsen experience unfolds. Packed with erotic and intense missions unlike typical onsen girls! She orally receives stimulating acts from male guests, and unexpected scenes arise using real soap mats. Uninformed and completely unprepared, Eri Ka remains tense throughout—so much so that she forgets to cover her body, causing her breasts to slip out and her buttocks to be fully exposed! This is no longer just a performance; witness her truly raw and real moments.