The instructor big sister took my hand and led me outside. At the sports gym's training ground, she stared hungrily at my sweaty body, whispering how being alone with me made her heart race, while gently stroking my cock. In the bath, she attacked me with her big tits; as I stretched out, she climbed on top of me, grinding her hips wildly until her body trembled and she squirted. Later, after finding Dad's porn magazine, my cock throbbed with excitement, so big sister taught me "correct masturbation." Learning how to use my dick made me realize just how amazing the adult world really is. One hour of big sister's perfect blend of kindness and eroticism.