This is... some pretty cringey writing/art. That girl is unbelievably cliche, constantly blushing and stammering. And the MC keeps holding one eye closed which is definitely supposed to look cool but really just looks weird. The creator seems to have pretty juvenile sensibilities.
just remind me because I wont bother reading from ch1, this is the MC that was like an old dude good with the sword right? does he not wanna fuck the teacher or something? come on author be realistic for fucks sake