The character development in the series especially the light novels is so immense and the way their relationship grows is so satisfying its definitely worth giving the anime a try, tho the story is completed through the 10 (going to be 12) light novels that are also EXTREMELY WELL WRITTEN and give a satisfying conclusion as well.
Though it might seem like the ending is incomplete in the anime this is because there is enough content for at least another 2 seasons which is why the series might seem half way done, because the plotline doesn't end there (you can finish it through the light novels which are actually very enjoyable and interesting to read).
