Pro Lesring: Ring Out!!

Somewhere in Tokyo is an underground club where important political and social figures gather to watch an unusual sport. Two women are put in a caged ring, in revealing clothes, and grope each other while wrestling. Whoever comes first, loses. No holds barred, and the loser has to endure any humiliation the winner asks. Into this ring comes a young girl named Aya, forced into slavery by people to whom she is nothing.

[From Craxton's review made for Interactive Fiction for Grownups]