Devil's Line. It's kind of edgy and over the top, but something about the romance in it is really compelling to me.
Also I'm apparently the only person who actually enjoyed Mayoiga as a horror/thriller and not a "so bad it's good watch". The ending's a little weak, but I loved watching it as it came out and trying to figure out what was going on.
There's a probability that the upcoming Anime Series I'll mention may not be underrated completely。Since they may have gotten the appreciation it deserved half way while it was airing。But from Romance to Super Heroes & let's not forget the Sports Series as well。Here are a few Anime that I believe to be under but enjoyed to the fullest。
✩Sakamichi no Apollon
✩Sangatsu no Lion