The sensitive areola is discovered by her younger sister, who mocks and plays with her weak nipples. (4 Shishido Riho, Amamiya Ayaka, DRPT-122)

"My nipples are 'mine'!" The doting older sister has a secret: she has "weak nipples"! One day, her younger sister catches her masturbating and playing with her nipples… For the athletic younger sister, who calls herself "Boku," this is too much of a stimulus, sparking a strong interest in her older sister's nipples! From that day on, the older sister's nipples become the younger sister's possession! In the bathroom, in the kitchen, she constantly kneads, licks, and sucks them! She even uses her secret weapon, "tentacles," to fully develop the pleasure of her older sister's nipples! But in the end, the older sister, having gone too far, turns around and punishes her with nipple play…