In my early days of being into the anime medium, there were a couple of shows that I loved so much they became number 1 and 2 respectfully. Shakugan No Shana was one of them and I really loved it that time. That was... 3 - 4 years ago-ish?
Now when I tried to rewatch it, I just... couldn't. Unrelated, but I tried doing the same with Bleach, even buying the boxset to an extent. Still couldn't get into ti, so I might as well try pawn them off to someone who wants them.
Anyway, back to Shana. But uh, I really liked the first two episodes. They were the actual highlights of the series. The first episode shown a really interesting premises of the other world, whilst the second is about a girl in the class who going to disapear because she died in that other world [basically, when they die in the other world, they create a flame to keep them alive to reduce the shock and stability issues]. It created a really interesting premise and that Yuji just couldn't believe what he's been seeing.
...then the romance kicked in and everything went to ****. I would tolerate it if Shana was the only love interest, but nope, they had to bring in a ******* love triangle. And that took up the majority of screen time if it isn't 'demon slaying' or 'incest scenes' [though I approve of the incest... wait, I'm not attracted to my sister].
The second season was much worse, as it tread the events of the first one and thrown in a third woman to make things worse.
So yeah. Shana I used to love, but now I absolutely hate it. It's more high school romance cliches than demon-slaying 'LETS EXPLAIN ABOUT THE OTHER WORLD".