BBY/ABY is used to position items along the Star Wars Timeline. BBY refers to Before the Battle of Yavin. ABY refers to After the Battle of Yavin. The Battle of Yavin in Episode IV: A New Hope occured in 0 BBY/ABY.
Kir Kanos, the last surviving member of Emperor Palpatine's Royal Guard, is ready to settle a score with Luke Skywalker and those others whom he blames for the death of his Emperor. But standing in Kanos's path is his former adversary and almost love interest Mirith Sinn. And both of them have become pawns in a secret plot by an Imperial cabal!