Uhmmm...he’s a teen aged boy. They are, at the very least, curious at that age, am I right? His mommy probably didn’t have anything to do with his interest in reading about sex. There’s nothing wrong with the boy wanting to read about sex - the kid’s innocent. The teacher - not so much. He’s been teaching and advising at the school for years; he must know what is expected of him as an educator.
True. But what is this particular book about? Homosexuality, Heterosexuality, Bestiality ?
50 Shades of Gray sounds rather 'liberal'.