Gein

Gein is the last remaining descendant of a small group of people who mastered the art of mechanics in the Middle Ages. He creates puppet like suits out of the corpses of dead people most notably the Iwanb series. He is actually an old man yet he is very strong due to controlling his heavy puppets for so long. The diamond edged steel wires he uses Zankosen to control his puppets can also be used as a weapon as they are sharp enough to cut flesh and break bone. Gein just wants to test out his creations and needs to be around men of battle to do it since according to him the forefront of technology is always in battle. This is also the reason why Gein joined Shishio. wikipedia