Theres this girl whose always made fun of me for being flat as a pancake and so during the summer I saw the perfect chance to get some revenge. A few of our friends were going to the public pool and I offered to tie her bikini and I ended up tying it super loose. When it was her chance to go down the waterslide, her bikini top fell off when she got to the bottom! Everybody started laughing and since then, she doesnt talk about my flat chest!