Ria is a new teacher. This summer vacation, she will go on a field trip with another teacher to survey locations for the students' tour. However, Ria is unaware that her colleague has been admiring her seductive body for a long time. He discreetly spiked Ria's drink with an aphrodisiac, waited for her to enter the steam room, and followed suit. The drug quickly took effect. Ria succumbed, allowing her colleague to molest her naked body. Upon waking up, she was in a haze, obedient to his commands. Ria's body became extremely sensitive, itching, craving to be relieved by his cock. He then used this incident to blackmail her, forcing her to continue satisfying him. As Ria gradually became addicted to the aphrodisiac, she actively sought him out, becoming more willing in sexual encounters, voluntarily complying with all his perverse demands...