XJX419: Sister's Practical Lessons in Fucking, from Kissing to Creampie

The older sister guides the younger brother through the mechanics of sex, starting with deep kissing and moving to oral, then positioning herself on top so he learns the rhythm of thrusting, all while she coaches him to go harder and finish inside her. She also uses her big breasts for a titjob, demonstrating different angles until he's spent. It's a hands-on tutorial where the lesson ends with cum leaking out of her.