Riko is my classmate and childhood friend. One day, while we were studying together for exams, she told me, "You can touch me," and I got to touch a girl's breasts for the first time. Since then, I couldn't take my eyes off Riko's breasts, whether at school or after class. Every day, whenever I had the chance, I secretly touched her, and I soon realized how incredibly good her nipples felt. Our relationship continued to grow even deeper.