“He knew there was a gray area.”
What gray area? Either she attained the age of consent or she didn’t.
It doesn’t matter, she is a minor.
It also should be illegal with anyone abusing a position of public trust or authority to gain sex over an inferior/student. A boss who makes it plain to an employee that their paycheck depends on sexual favors, a college professor giving better grades to a student they are sleeping with. It is all wrong and should be firing offenses.
If its a minor, they should just be shot.