As someone who's 40, and have only seen 2 animes, I have to pat myself on the back for knowing exactly where the source images came from. In retrospect teenage me watched some weird shit.
My memory of it was that a 25 year old gang member decided to become a substitute teacher at a high school for the sole purpose of perving on 16 year olds in high school. Somehow he got transfered to being a full time teacher in middle school, and he had to rescue one of his 12 year old students from making underage porn to support her family, despite being very VERY against doing so morally. Then he swoops in to kick everybodies ass for making child porn.
I also remember they had a running gag of doing this creepy smile thing. Everytime anyone did it, I always got creeped out. And somehow NONE of this raised alarms with me as a teenager, but adult me is like "Wow, in retrospect, that show was pretty fucked up."
I mean it definitely couldn’t be made nowadays, but I did think it was kind of interesting because it focused on outcasts and the very real sorts of awful situations people like that might have gotten into that the rest of society just kind of refuses to even acknowledge.
But yeah it is undercut a bit by the whole weird pedo thing Japan still has going on to this day.