Write a giantess story starring a sweet, music-loving teenage girl named Pianitchi who, after finding a poster for "experimental growth tests" in her mailbox, available in her town and realizing she's eligible, decides to participate. However, the machine regulating the volunteers' doses mistakes Pianitchi's dose to be much larger than it should be, and Pianitchi quickly becomes enormous, rapidly growing to 8 feet tall, then 20, then 50... 100, 200, before finally stopping at an incredible 300 feet tall, big enough to be seen from miles around. Detail the accidental chaos and destruction she causes because of her explosive and spontaneous growth, and her subsequent embarrassment upon realizing everyone below can see her panties. Just when she thinks her situation can't be any more humiliating, however, her flat-chested boobs suddenly explode in size, leading to her shirt tearing as her boobs become enormous, making her even more mortified and noticeable!