Female Teacher Caught Forcing Students To Have Sex. Married Teacher â€˜forced Students To Have Sex With Her To Get Good Gradesâ€™ At Colombian School. Yokasta M, 40, groomed teenage boys at at an undisclosed school in Medellin, Colombia, and would threaten to fail them if they did not sleep with her. The teacher approached her students aged 16 and 17 on social media or asked for their phone numbers in class to â€˜help with their studiesâ€™. She allegedly used WhatsApp messenger to send explicit images and proposals to her students. Dozens of photos sent to the teenagers show Yokasta M. posing in underwear or a bikini, and sometimes only covering her modesty with her hands or fluffy toys. The married 40-year-oldâ€™s cover was finally blown by a father of one of her victims, who checked his sonâ€™s mobile phone.