Kain - Manga
Summary
Kain is a story about a blue eyed boy wandering the countryside. He happens to be in a town controlled by "kidoushi". These "kidoushis" are people from the newborn country of Ren, who have a machine in their body, giving them power equal to an army. The power of the kidoushi is determined by the amount the gigai (the machine) take up in their body.