It is a very sweet and pure love comedy between a teacher and a student.
On the other hand, this kind of relationship where one holds a position of power and authority over the other is the recipe for disaster and abuse.
There's a reason teacher/students relationships are "frowned upon". Kind of like Boss/Worker, Brother/Sister, Parent/child. There's a clear structure of power on these kinds of relationships that can be used to dominate and abuse the partner.
I never personally experienced any of those abuses, and I am by no means an expert in abusive relationships and teaching ethics. But Just from reading what people went through in these scenarios, it makes it clear why its a bad idea.
But this manga is by no means a story of abuse.
Spoilers from now on:
The manga seems to be aware of this, Rinko-sensei herself is aware of it and won't "date" Arase until he's 20 and no longer her student. Then this structure of power will be removed and they can stand in equal ground. I think this is a nice idea but it doesn't change the fact they are in love while still student/teacher, and that's exactly why this manga is good.
The manga's charm is in the subversion of their power dynamic.
Rinko is a strict teacher that holds power over the "lazy" student Arase. This changes when they fall for each other and Arase takes the role of the pushy and flirty romantic that holds power over the shy and evasive teacher. It makes for good romantic comedy
But then again, this is "the best case scenario" for a teacher/student relationship that doesn't show any of the "bad sides" of what could happen (until now) and it might influence the minds of young readers.
Overall I really like this manga. It is definitely a cut above most slice of life manga out there
