The Draygon books I've been working on came while I was binge playing Dragon Age Inquisition. Now it's been so long I can't remember what my original idea was, but as I actually wrote it the first book evolved well beyond Dragon Age so now the only resemblance of the game is I have a version of tranquil mages. I call them the Vanguard Mages and they're forced to wear bracelets that zap them of all freewill and thought.
I had another book called Lady of the Mysts that was inspired by the Aes Sedai in Wheel of Time. That one ended up staying a little TOO similar to the Aes Sedai for my liking so it needs to go through some major rewrites at some point so it no longer looks like an out right copycat.
The final book that was directly inspired by something is a book called The Thirteenth Day. I was reading the Raven Cycle books and really liked the Ghost character in it. Made me think about what would happen if he wasn't actually dead but just trapped while his body was dying. I know that story has actually been done a million times before in both books and movies, but it's still what I wanted to write. So I wrote a kind of love story where the boy could see ghosts and was supposed to use his ability help them crossover. But the girl ended up not being a ghost, just treading that thin line of life and death.
Dragon Age Inquisition! I played that game(but never got around to finishing it 
)
Your stories all sound interesting though the last one sounds sad as well
My upcoming webcomic, Celestials, started off as a sort of parody of Hetalia. Basically, the premise was "what if Hetalia... but with planets instead." I was too lazy to do research on space and stuff so I kind of made up my own lore. And over the 3-4 years I've had the idea, it managed to occupy parts of my brain space enough to the point that the lore and story is incredibly different to the ones I originally had. It was originally a stupid comdey slice-ofplife feautring aliens, and is now a fantasy webcomic set in space.... featuring aliens.
Sadly, Celestials isn't released yet, and it's not gonna release in a while. Life stuff and the occasional writer's block makes it so progress on writing it has kinda grinded to a halt 
but I'm excited to share it on Tapas when I can!
I wanted to do a comic remake from my childhood, which Inspired by Sonic the Hedgehog SatAM, and some Isekai stories. It's more battle shounen-like. Over the years it has becoming more and more elaborate & detailed in my head: a large cast of characters, plots and places... I feel that it's too large and ambitious for my first webcomic.
So i decided to tell a much smaller scope, intimate and grounded of a story: a backstory of a certain new member of a group. It's all happening in the same universe i created, just on a different place, story tone and drawing style.
Cool question. I actually fell into reading a lot of BL, specifically werewolf BL last year and I started to see kinda of the same plot over and over again. There really wasn't anything new and I kinda want something more than the typical "alpha claims me" or "i didn't know I was a werewolf" so I decided to write my own. And after that, I have been writing ever since. And this is my first time writing so I really have been enjoying myself! Cheers!
I came up with mine after thinking of random scenarios that my characters, that I drew separately, would get into together. Then they became a trio and I made the comic.. Some influences from short comedy/Slice of Life anime and long comedy/action/Slice of Life anime is in there XD
I started mine with a simple character that I made for fun one day and gave him supernatural powers. I wanted to expand/elaborate on said powers so that it would be easier to explain and well it just all went from their.
1: Designing the Characters
2: Me thinking to myself: "How can I hurt youuuuu?"
And then a story happens 
2: Me thinking to myself: "How can I hurt youuuuu?"
The mind of every series creator to their own characters XD
oh yeah mine really spun out of control
so initially the titular character, vainglory, was a D&D character. I gave her a couple fun, energetic traits, but she was not complex. then, gradually, as we went through the first campaign, she became more and more complex and developed a more and more detailed backstory. slowly, she began to interact with the themes of romance, humanist and hedonist philosophy, abuse and self-loathing, and compartmentalization
several years later, I drew her buff and I was like "I need to continue drawing her" and thus the comic was accidentally born
There was just too many BL comics out there. So I wanted to make the last one.
@wocalichofficial what an interesting way to start a novel. With a chant.
I wanted a gothic romance about two women who get locked in a medieval castle while searching for an artifact (it was a collection of rare pottery illegally exported from Vietnam by the French.) one lady was of Jamaican descent from Montreal, the second was a Vietnamese with the knowledge of the artifacts being stolen from the destroyed museum through her family. The French family was the villains.
Seeing how that set-up would be too hard to find audience for on-line, I change to the Italian mafia family power struggle that puts the two future lovers in the dungeon, made it straight, American and the bad boy with tragic past for the love interest. Once I decided to write First Person, Present Tense, I had to make the main character un-identifiable. I also added a bit of deSade and CIA background for the dungeon