Well is been a while, thanks for coming back so we can hopefully get it done and forget about it for good.
Let'see how well I remember it.
The story ended, somewhat okay then the author decided to do a WHAT IF, which is neat sure, but in one of the worst way possible, by having the protagonist just take a sudden swerve near the end of the story to take a dump on the story (and later in his own pants see my comment about it from 1-2 years ago), get with an even younger girl just so the author can cockblock him even harder and make him much more of a timid, scaredy cat......as seen here.
Also the author had another Manga after this one, but at 23 chapters we can safely guess it was axed, a (female) teacher (male) student romance, penultimate chapter she comes onto him, but in typical japanese MC behaviour he stops her and then a timeskip at the end of the last chapter................how "riveting" .