I am not a big fan of sexfight stories with many characters. But there are some here who do it well. How about a sexfight story between two rival female Kabbbadi teams?
Kabbadi is this asian sport:
Kabaddi - Wikipedia
Its a bit like wrestling.
Here is an example:
https://www.youtube.com/watch?v=-uUqFEq4KIs
it gets really dirty with lots of body contact and sweating.
One more:
https://www.youtube.com/watch?v=60-ERiAEXQI
Somebody should write it.