One warning before I begin: DO NOT POST STORY IDEAS. Yes, I know people might have ideas as to where you think the story could go; but that's not the point of this exercise. Once a first draft of a story is complete, I do sometimes show it around to other writers I know looking for feedback; and sometimes I do get ideas of how to change the story, to make it better. But I can't accommodate that during the process of writing the first draft. If people start suggesting directions for the tale, then I'm not writing my own story, I'm writing theirs, and I'll have to slam this window shut.
And now, on with it.
The creative process began, of course, when I took a look at the six final opening lines. I finally chose the one I did because it reminded me of the Star Trek: The Next Generation episode "Half a Life," in which a society has evolved with a custom called "Resolution." These people solved their old age problem by requiring voluntary ritual suicide at the age of 60, and the story is about a man who is convinced to fight the custom when his time comes, and what happens to him.
I will often look to other fiction for ideas, in something that Lawrence Block once termed "Creative Plagiarism." The idea is to figure out a way to rip off a story without actually stealing it. So since this opening line led me to consider the concept of voluntarily ending one's life, I decided to start typing out some dialogue and description to accommodate the concept.
In the Trek episode, people end their lives with a party with their family and friends, called a "Resolution." I decided I wanted to incorporate that concept into the story, but I didn't want to steal the name for the party. Too close to real plagiarism. Thanks to gnomi, I now have a good name for the custom and title for the story, which I gave above: "Denouement."
The pieces I have now paint a society where the Denouement is a codified ritual, but it opens with a man being asked to hold off, as his last guest wishes to tell him a story. Right now, the story is vague, but it leans towards an alternate version of the holy tale explaining why the society adapted the Denouement; the main character (named Andrew, for more Tuckerization of agracru) will soon discover that his last guest is a heretic, who rejects the Denouement concept and urges Andrew to do the same.
And where will the story go from here? I've thrown in a crystal ball to record Andrew's "soul." Or maybe there's a hidden colony of older people to which he can be spirited away. But that's the nice part about the beginning of the creative process. I can do anything I want...