Here's a story idea that occurred to me that I would never write, and don't have time to - What about making a story about being the plaything (or stud) of a major sports team (male or female depending on preference)? Like, names of the athletes, pre-game (reverse) gangbangs, etc. Support the team. Seems like a diehard team sport fan fantasy come true... Even more - with variables one might be able to allow users to change the team name and positions. It'd mean the descriptions would have to be more generic, but Team Name could be a variable, then there could be positions like star forward, point guard, whatever (depending on the sport) where the names could be set - allowing anyone to have their slut/stud for the home team fantasy.
An advantage of the set-variable approach would also be that the story might stay relevant longer, since team rosters switch up yearly.
I once had the idea about a hot female (or futanari) coach, who is extraordinary successful in training a male soccer team with quite unconventional methods (femdom). As you all probably know, most professional soccer players are whiny bitches... their favorite activity during a match seems to be squirming on the ground and crying. So it only seems right that they could easily be dominated by by the all female staff, and turned into submissive little bitches. ;-) It could all begin as a punishment (for example getting strapon fucked in the ass if playing too many bad passes. Or build the humiliation more slowly), but it could quickly turn out that those guys play much, much better, after being put in their place. And so what began as some kind of joke or dare could soon become a regular thing and approved training method. They could ultimately get the players girlfriends and wife's on board, and soon not only the regular pre-match plan would consist of humiliating and dominating the guys in various ways, but their whole life would be turned upside down, as femdom begins to influence their behavior in almost every waking moment. And their is always the looming danger of public discovery...
I’ve heard tales of guys being the sort-of “groupie” for female bands so sports wouldn’t be too far off.