Even when together with friends, their purely platonic bond gradually takes a lewd turn. Two close girlfriends they met on the street, bored and with nothing to do, decide to try mutual masturbation for the first time. Facing an erect cock in front of amateur girls, they begin showing expressions mixed with hesitation and curiosity. Slowly, their female instincts awaken and erotic feelings start to bloom. "So you... always do it like this..." moans the horny friend. Uncontrollable excitement and lust continue to build higher and higher. Their relationship moves forward into a point of no return.