As previously speculated, the content will allow you to fight against Final Fantasy XIII protagonist, Lightning. Beat the pink-haired beauty, and you'll unlock her for use in your party.

According to Siliconera, future DLC will include a costume pack and new story content. The latter will "enhance the experience and complement the narrative of Final Fantasy XIII-2 with storyline branches for key characters in the story".

Apparently, that Ezio costume is on the way too.