A novel where MC is an entity or system that takes care of other people's characters.

I've read many web novels, but I haven't found anything like this. That's why my mind is telling me to "search for it," and here I am asking for expert help.

So, give me several novels that feature a main character who helps the supporting characters develop. It's similar to the Dungeon Master in Dungeon Run, where the protagonist guides the story.

— It's okay if it's a system.

(Note: I don't want Dungeon Core novels because I've already read them and they're not what I'm looking for.)

(This is my first time, so I apologize in advance for any missing marks.)