That sounds like a great concept for a fanfic! Here’s a more detailed outline and some ideas to help you develop your story, Honkai Star Rail: Herrscher Of The Stars.
Title: Honkai Star Rail: Herrscher Of The Stars
Summary
My name is Caelus. I don’t know much about my past, except that I am a Stellarons. Only Mr. Welt knows my secret. Recently, a mysterious entity known as the Star System has started communicating with me, insisting that I am the new Herrscher of the Stars. I’m not entirely sure what that means, but it seems to come with a variety of powers. Now, I travel from planet to planet aboard the Astral Express, helping its passengers solve their problems, all while trying to uncover the truth about my identity and the responsibilities that come with my newfound powers.
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MC: Caelus
Ship Caelus X Harem
