Do I need authorization to write doujinshi?

Writing doujinshi required authorization. Doujinshi refers to the modification, adaptation, or re-creation of the original work to create a work that is different from the original work. In some cultural fields, doujinshi is viewed as disrespectful to the original work, as doujinshi often disrespects the theme, characters, and plot of the original work. Therefore, writing doujinshi required authorization. In most countries, this is called "copyright law" or "copyright law", which requires authors to obtain the permission of the copyright owner before they can create. If you write fanfiction without the permission of the copyright owner, then they may be at risk of legal action and compensation for the violation. Of course, some authors might be authorized by the copyright owner to create legally. But if you want to write doujinshi, you should ensure that you get permission and comply with the relevant provisions of copyright law.