A big-titted older sister introduces an experiential course that awakens the mysterious erogenous zone known as the "Spence gland"—a pleasure point located within the breasts. The moment curiosity turns into action, each slow, deep kneading intensifies the sensation, sending waves of pleasure coursing through the entire body, steadily elevating arousal toward climax. Instead of massage oil, her own slick arousal continuously seeps out, soaking her lower body. Even during the final stage of treatment using a thick cock, breast massage remains a constant, unlocking entirely new dimensions of pleasure. Once consumed by this overwhelming ecstasy, there's no turning back.