This feels an awful lot like Day 26 last year, which I struggled to answer and still feel a bit at sea over. So here's the story of a particular bit of inspiration for a particular part of a roleplay game - specifically, Svetlana's rather ambiguous father.
My elder sister recalled reading and rereading Maurice Sendak's Outside Over There to me over and over and over again when I was that age of child where you want that. Something about the story held me utterly gripped - she was terrified, but hid it well, seeing herself in the role of Ida, I guess, whilst I knew that if anything happened my big sister would save me, just like Ida saves her sister.
I saw the end of Labyrinth when I was young and the film seared itself in my mind such that maybe 15 years later time stopped when I found the DVD on my housemate's shelf and knew I'd finally found the film.
A huge Pratchett fan, I put off reading Wee Free Men because Husbit said it was too clearly aimed at children - but I loved it. It carried that same theme. I recently gave a copy to a 9 year old friend, and am terrified she won't love it.
I have an idea for a novella on these lines too.
I read Juliet Maurillier's Heir to Sevenwaters because it has that same story, of a child taken by the fairies. However (and in an attempt to avoid spoilers), what really caught me was a secondary storyline, revolving around the male love interest. It turns out, his father is a powerful fairy who went around impregnating women in the hopes of getting a male heir. You meet a much older woman who transpires to be his half-sister...
And that fascinated me. I wondered what it would be like to be the abandoned daughters - the novel implied there were many. And then fey blood is one of the sorceror types in Pathfinder, so I gave it to Svetlana and invented this whole backstory where her father was a powerful sorceror in an ancient tribe of elves who intermingled with the fey, he more than the rest, eventually reaching a point where he's maybe more fey than elf. And on some whim, he decides he wants a son, so finds a wife, and bores of her before she's produced more than daughters. On to the next one, and the next, until he stopped bothering marrying them and merely seduced the women - his power when Svetlana was conceived such that he didn't need to physically be there, but came to Natasha in a series of dreams.
I picture him as very ancient but still youthful. Mysterious, capricious - and still seeking a son. I don't know if Svetlana is the most powerful of his offspring, but all have some magical talent. I left the rest to the GM. He says he has ideas...