If you want to prevent others from registering a trademark in Class 16, you can consider registering a trademark in Class 15 or Class 17. In the 15 categories of registered trademark, you can choose the "trademark name" category. This category allows you to register a name but does not allow you to use it as the brand name of a product or service. Marks in this category are usually used for creative products or services such as novels, poems, and literary works. In the 17 categories of registered trademark, you can choose the "novel, poetry, literary works" category, which allows you to register a name but does not allow you to use it as a brand name for a product or service. Marks in this category are usually used for creative products or services such as novels, poems, and literary works. Of course, the registration category is not foolproof. If you have a unique business idea or intend to use it for products or services, you can also consider registering a trademark in the 16 categories. However, in the 16 categories of registered trademark, you need to provide a more detailed business plan and undergo a more rigorous trademark review. Therefore, before registering any trademark, please make sure that you are fully prepared.