Warning, slight spoilers ahead.
Jump gets the scoop on FINAL FANTASY XIII-2 this week (with Famitsu continuing coverage in their next issue), this time, letting us in on a few story details surrounding the game.
The magazine mentions that Lightning is in fact the only remaining relative of Serah. She’s gone off alone, now fighting as a knight to protect a shrine of the Goddess Etro in the land of Valhalla. There are some images of her with Odin in the article.
As for new main character Noel, he is actually from the future. As the last surviving human being from his world, he returns to the past in hopes of changing that fate.
Source: http://www.novacrystallis.com/?p=1406
Also Lightning was obviously fighting as a knight to protect Etro's shrine. The only other thing is that she wants to find Vanille and Fang. She wants to save them.
reaction to the awful "I'm from the future!" reveal that will no doubt happen. At least we're prepared for unoriginality and convoluted tomfoolery this time around...
lol