Yamamoto Haruka is an office lady working at a trading company in Tokyo. Her biggest concern is the constant attention her chest receives. Her large breasts are impossible to ignore once seen. Starting from elementary school, she began developing early, and since few girls in her class wore bras, she was often teased by boys. By middle school, she started receiving sexualized gazes, and even during swimming class, delinquent students would approach her. In high school, she had her first boyfriend, but grew disgusted with how obsessed he was with her breasts. A turning point came when she moved from the countryside to Tokyo for university. Surprised by the excitement of city life yet feeling lonely, she was approached by an upperclassman from her club. He was a playboy with exceptional skill, and he manipulated her breasts in countless ways, gradually awakening her sensitivity. His techniques left a lasting effect—now any man's touch on her breasts sends waves of pleasure through her. Today, she takes pleasure in using her chest as a weapon to lure men she's interested in. Yet, the constant attention remains a source of stress. She struggles with deciding which man to approach.