Elyon
I doubt a lot of people would actually buy a jacket like that even if they'd find it cool. I'd go with the stuffed Kasogonaga if I were you. If it's cute enough people who don't know your story might buy it as well while I doubt the same would happen with a jacket. The book seems like a waste. I assume most of us are reading at webnovel.com instead of hardcover books for a reason. And people having read your story on webnovel will probably not buy a book version of it. They know the story already after all. At least I wouldn't.