For people who answered Valkyria Chronicles. Snipped from the wiki:
Alicia is the 19-year-old heroine of the game.
Isara is Welkin's 16 year-old adopted sister who cares greatly for her comrades.
Edy is a 17-year-old militia shocktrooper.
Homer is a kind and pretty 15-year-old boy with a frail constitution who serves in Squad 7 as a engineer.
Susie is a 19-year-old scout.
Though, I guess outside of Alicia, the other characters aren't really what I'd consider main protagonists.