I read a few things that you got, just the first chapter, though. My attention span is horrible. As for actual advice, I'm not the best writer myself. I read books and kind of learn from what I read. How to structure, explain, grammar, and plot. I need improvement myself. But from what I've read you should space out your paragraphs more (I actually need to do this myself, it's something new I learned). Your writing seems fine to me and your explanations seem okay so far. By writing, it'll continue to expand so keep going. But make sure you're spacing after periods and commas. Also when you write, for example; "Natsu said, fiddling with his scarf." Commas after said or exclaimed or whatever you use and then continue with what they're doing. (I'm literally the worst at explaining). Comma or punctuation after someone speaks. "Stop burning every building you look at, Natsu!" Gray yelled, punching Natsu's stomach and knocking him unconscious.
I've seen Fairy Tail (: haha!
For the most part, everything else seems fine. As you write you'll get better and better. I'm still learning. I always catch mistakes or plot holes in my writing/story.
Speaking of plot, if you plan to write a story, as in not one shots, like an actual book, I suggest planning. It helps so much.
I hope this was helpful. I love helping people in any way that I can.
As for arc v, you should watch it. It's amazing! I love every minute of it! I love the plot, they seem to be building it quite well. It's a good way to see a slow-paced storyline, and hopefully it'll have a big impact when the important stuff hit. If you have any other questions, feel free to ask.