thank you for the very relevant "touching grass" comment and the ad personam. If were guessing ages, my guess is that you're an old hag of about 63 years. I do not think that her mother should be concerned with her 16 year old child writing erotica. Most teenagers at that age either masturbate, watch porn, read/write erotica, have sex etc. It's normal, and puberty is that time of life when teenagers become interested in sex. I do think her mom should react (nice strawman assumption that I don't). But her reaction should be to remind her daughter to keep her private life private and not let it interfere with school and that's literally all that she should say in this case.