If 18 is the legal age of consent, I don’t see a problem. Only if it started before the age of consent.
And it’s irrelevant if you think the age of consent should be higher.
If “teachers” wish to be thought of as “professionals”, they first need to behave as professionals.....and keep their peckers in their pants around their students.
The fact you didn't pick up on that - makes your comment and opinion “irrelevant”..... Right?