I agree.I guess he's having a hard time letting go of the memory of him being his student and all
it's good that it's not escalating too fast and first time a story feel like reality :)
It makes a refreshing change from all those manga where teachers have absolutely no boundaries when it came to their students.
Yeah thats what i really like about this manga like this teacher knows his boundaries.
This has been bothering me like i get he doesnt have sex with students which is the best. But hes 25 now and no longer student. I guess sensei is stuck in the past. And is feeling guilty.