Raising a Loyal Dog [Siblings]

[The heroine is a player. The hero has been sent to a class on proper conduct for men, and graduates with honors in high school] Zheng Yi only saw her younger brother again when he was eight. She didn't need another person in her life. So Zheng Yu had to become her dog. Training a dog takes patience. You have to keep him in check when he's angry and comfort him when he's down. You get to decide what sweetness and pain taste like, and shape every emotion he feels. And then... "Zheng Yu, come here." She shook the bell. The man, who wore no collar around his neck, hurried over and curled up on Zheng Yi's lap like a dog. Theme: Sisterly affection and master-servant devotion