OMG! This tread is gold!
I had been building a world for more than a couple of years now, and I must say I haven't tried to do something more ambitious like @Trapp, because of limitations of sceneries. I come to here to do/get inspiration for the kinkiest parts of the stories, and that leaves much of the action out. The specialization of my scenery is somewhat unique (c'mon, a military academy... In RUSSIA), and much of what I've done... now that I think of it, has came from TK17: The abandoned bunker, berger's shower room, Driver's scenes room (the one with the pool, there are stairs and a shower, have you noticed them?), @Sexvision's covid care, the sinuos room and now I'm making one for the romantic apartment.
But I need other locations and I believe I'm gonna learn how to make them, because I doubt someone would make a Russian Army barracks, for instance.
Now, about the world building. My stories are always based in our world. I don't know why, because I love super heroes' stories and mangas like Kill la Kill and 7 deadly sins to name a couple, but can't work with fantasy. It's easier to me make crazy stories in a "real world" like the Kakegurui anime (the premise to me is dumb, but I love the characters and their stories) than create a "Lord of the Rings" like world from scratch. The only fantasy lore I find extremely appealing, is Castlevania's, and maybe some day I'll explore that.
Most of my characters are women, and most of them have now a background and a somewhat complicated life story. Interestingly enough, most of my male characters are more like decoration.
And I use our world, because I know A LOT of history. It was my favorite class since I was a little boy, and grand strategy games from Paradox Interactive made me basically a nerd at geography (from the countries of my interest, I must say). So I can place a story in ancient Greece or Rome, the Bizantine Empire, the Holy Roman Empire and of course Imperial and Soviet Russia. I find a little troublesome use my own nation, because our history hurts me, a little; but I need to use it for the sake of my universe.
I like to think in alternative history, and what ifs... that's a different kind of "realist fantasy". So, maybe I cheat a little, again, using our world as a starting point.
I love character profiling, that's why I enjoy stories by Trapp and @Morius. I must get into @Oz70NYC stories, because I enjoy them and every time I read a new story from a new author, I learn things.