As far as teacher x student love stories go, this one is fairly time and quite comfortable to read. There are a few that feel wrong, like the teacher is taking advanatge of the student or vice versa, but this one isn't like that. It actually feels quite realistic, or at least as realistic as a teacher x student story can be, plus it is very consensual, and, surprisingly, very sweet.
The teacher's whole,,, thing,, is that she's surper serious and morally upstanding, and this turns out to be the flaw that is keeping her from finding love because of the student she once had a crush on. mikoto is the cool, laidback open lesbian at an all girls school, that i for one can seriously relate to. There romance is sweet, it's gradual, and they wait till graduation before actually dating, so it doesn't feel bad to me in that regard at all.
I'm writing this after chapter 9.5, the toda special, so it might have changed in the future, but as of right now there hasn't been any sexual content (and if I'm honest, it doesn't look like there's going to be any for the forseeable future). This might dispel me from a manga usually, but honestly in this one i think it really works.
i hope the author creates more chapters soon!