LogFAQs > #976436097

The one thing I'll say about Vanille/Sazh that avoids spoilers is that Vanille needs to mature like Hope does. The definition of HOW and WHY she needs it is why Sazh is the one her journey occurs with compared to Lightning/Hope. Sazh couldn't give Hope the growth he needs(you'll understand why after a certain part); Lightning couldn't give Vanille the growth she needs(you'll understand after yet another specific section).

Again, avoiding spoilers, that's the most effective way to describe the situation. Fang/Snow is a bit more subtle. Won't touch on that though until presumably you've gotten further into the game.