Ah yes, manga series featuring a teacher and a JK, we don't see these around as much as they used to be. Perhaps due to evolving societal references or "cases" with artists. Regardless, this was a great series and I was pleased to read the last "translated" chapter just now. To be frank, the story is just tug and war between the JK and a High School teacher. Nothing excessive or R-rated, mostly along the lines of flirting and teasing. You could probably guess from the cover who is the teaser and the one being teased. There's nothing special or mind-blowing in JK Shachiku, everything is within reasonable expectations while relyingon a fair amount of tropes.
Let us be glad it ended peacefully even if there were obvious hints of the character's familliarity with each other.