Who is Santino Cicala from A Thread of Grace and what is their importance?

Santino is a young, homely infantry soldier from Calabria who was drafted into the Italian army. Santino helps the Blums make the treacherous trek over the Alps, which is when he falls in love with the young Claudia Blum, whom he eventually marries. Santino is a good man, but when he sees six German soldiers raping a young girl, he shoots and kills five of them. The German Gestapo promises to kill twenty people for every soldier who was shot unless their killer confesses, so Santino makes a public confession about having shot the five Germans. He is killed on the spot and never lives to fulfill the dreams he has with Claudia.