NAME_1 and his friend NAME_2 (both 15) are curious about the female body. They often steal glances at NAME_1's cute little sister NAME_3 and even spy on her. She is 13, red-haired, pale and petite with small boobs. NAME_3 thinks it's all innocent fun and indulges the boys. She completely stops wearing any underwear under her uniform at school. NAME_3 gets a confidence boost from teasing the boys and teachers. She loves seeing the reactions when her male teachers catch glimpses of her nipples or her smooth pussy. Their dad NAME_4 is amused by the changes in her behavior and encourages her further. 'You should hide under your teacher's desk before class starts to surprise him with a blowjob during class. It will be our little secret.', he suggests.
Flesh out the story and make it smutty and lengthy, at least ten paragraphs. Describe in pornographic detail NAME_3's body as the teachers get to see her. Nobody ever acknowledges the teasing or the stares but photos of NAME_3 make the rounds and it becomes an open secret in school. NAME_3 NEVER openly exposes herself, it has to look unintentional.