The ending makes the whole thing worth watching. And, once you have finished watching, you can then troll others by convincing them to watch this anime as well.
I feel like this is kind of a rite of passage anime. A typical trap where, the first episode seems fine, so you watch one, and then you have committed yourself to watching more. You slowly but steadily realise that you have made a huge mistake, but you keep watching episode after episode, hoping something will change. And then, you reach the final episode, which gives the most satisfying feeling I have ever felt watching a show. It makes it all worthwhile.
Probably the worst thing you could do to yourself is watch this anime and then give up half way through. I finished it in 1 day and I'm glad I did.
Also you may get PTSD from this. And this is probably what'll convince you to share this anime with others. Or make sure they never ever see it, depending on what kind of persion you are.
