My sister's feet had a mysterious, fetishistic curve, almost like a woman's genitals. Even though they belonged to my own sister, I couldn't help but be drawn to them. One day, I got caught sniffing the socks my sister Ichika had taken off. As a result, she made a proposal: "Pay me 100,000 yen and I'll let you use my feet for a whole day." Overcoming Ichika's initial resistance with adult authority, I forcefully indulged in using the bratty little sister's foot pussy. Her feet were subjected to all kinds of stimulation—licked, sniffed, and used to trample. The once-sassy sister gradually transformed into a woman's face. We experienced sex that transcended family boundaries, warm and heartfelt. The moment my cock touched Ichika's feet, I felt for the first time like we had truly become siblings.