Adaptation of a game, might be missing a tag or two in that regard. You can check out a demo for the original on Steam too if you'd be interested in that end of things. I think an episode or two of the Tales of Zestiria anime adaptation was actually about the start of this story too. So there you go, including this since there's chapters missing you now have a bunch of options for getting just a taste of this before probably having to buy or pirate the game to see how it ends.