The female character is a teacher in a private high school. Her dressing is unlike a teacher that she supposed to be. However, she is a total pain in the ass for the students (and/or their fathers) when it comes to shelling out grades for assignments and detentions.
The secret was exposed when one of the student (or the dad) checked their sibling phone and found she has been exchanging obscene texts with. In confidence, she trusted that those would get deleted but obviously that didn't happen.
He/she was upset reading the messages. He/she then blackmailed the teacher if the principal or cop finds out she would loose heer career and possibly going to prison.
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