Suicide Gambit. Suicide Arc, #5

Six years ago, Tishla led Suicide and her two young charges to Hanar. There, they gathered forces to retake the stolen world Amargosa. Since then, Tishla has strived to build a new world free of the shackles of Earth and the Realm's Throneworld. Now, six years later, a coup has sent Tishla fleeing to Suicide for help. Together with Suicide's son-by-choice, JT Austin, she must smuggle Tishla into the Realm to the one man who can save Hanar.
The move will cost Tishla her freedom, but the alternative is worse. Yet an old enemy has a score to settle and demands Tishla in bondage to repay a perceived debt. When JT challenges this interloper to single combat, Suicide must step into the arena for a bloody battle. If she fails, she lose the son she never had, Tishla's freedom, and an entire world.