Star Sister

Description for STAR SISTER by Juanita Coulson:

Renee Amos was a dreamer, dedicated to righting wrongs and championing under-dogs. But she never dreamed that there were others like her on alien worlds, also fighting for justice. Then two alien Arbiters, on their way to a distant planet to negotiate a peace treaty, accidentally picked up Renee and transported her with them. Suddenly she found herself on a strange world, with no way to get home and no choice but to join the Arbiters' mission.

But bathing City Hall had hardly prepared Renee for interstellar politics, and years of advocating pacifism were no preparation for stopping the destruction of entire star systems. For Earth itself was in the line of fire, and to save it, Renee would have to learn not only the ways of power, but also to kill...