I recommend I Am the Male Lead of Doujin to you. This is a novel about the infinite universe. The male lead can play different roles in different worlds, including Attack of the Giant, Tokyo Shizuka, Naruto, and so on. If you are a fan of Flower Man, you will definitely love this book! In addition, you can go to the library to download the Doujinshi package. There will be more works that you are interested in. I hope you like my recommendations.