Help us answer these unanswered questions! Take #3!

Question

The last "Help us answer unanswered question" occurred almost 7 years ago. So, I am thinking to reviving the activity as there are lot more users now and there are lot more new shows that released during the last 7 years. If we engage in this activity, the main page will look more active rather that the community bots bumping old questions. Currently, the percentage answered is 86%.

As holidays is around the corner and Winter bash is coming, users might have some free time to answer some questions and earn some hats as well.

I am classifying the questions into two categories:

1. Question focusing on one particular anime or manga
2. Question focusing on a broader area in anime and manga domain particularly questions with tags anime-production, tropes, japanese-language, culture, manga-production, anime-history, merchandise, resource, terminology etc. appealing to much wider audience.

I'll let the community decide what type of question should we decide to answer (which already has comments which can compiled to an answer) and after the decision, I'll post question list in the answer section.

Let's look back at questions we might have missed and see if we can get a little closer to the 90%.

Answer 1

The winter bash has started. So, it's a good day to flag off the activity. I am posting 10 questions from each category. I will update this list every 2 weeks (or whenever I will get time). Others are always welcome to recommend/edit the post with new questions.

Category 1 questions

1. Do Alkahestry have same limitations like Alchemy? Or some different limitations?
2. How could Madara use Kamui as the Ten-Tails Jinchuriki while Obito himself couldn't?
3. What is Saitama reading?
4. Does Touhou 9: Phantasmagoria of Flower View reference a specific real world event in 2005?
5. How many fingers exist and how did Subaru know the number?
6. How much of the manga does the Death Note musical cover?
7. Why wasn't Najenda's background story shown in the anime?
8. Why is calling Tohru amazing an insult to her?
9. Are there Blu-ray differences for Dragon Maid?
10. Are the similarities between Homura Akemi and Kiritsugu Emiya intentional?

Category 2 questions

1. Why do supernatural titles contain the word 'Code'?
2. Why do seiyuu famous for doing eroge still use alias?
3. When & where did the unnatural hair color aka "You gotta have blue hair trope" originate?
4. How does an official anthology for a manga series get created?
5. When did cold opens start becoming popular in anime?
6. What is the block used to symbolize the end of a chapter called?
7. Is it rare for two different anime to share the same OP/ED song?
8. For what reasons do manga get banned?
9. Is there a significant difference in production costs for Live Action vs animated OP/ED?
10. Why is "Hope and Despair" (希望と絶望) such a common theme?

Questions answered list will be posted in a different answer post.

Happy answering!