"I am the bone of my flames. Eternal is my body, and fire is my blood. I have created over a thousand flames. Unknown to death. Nor known to life. Have withstood pain to create many burns. Yet, those hands will never hold anything. So as I pray, "Unlimited Mokou Works."
Nope, bone. The anime translated it a bit clearer to ""I am the flesh and bone of my own sword." Though the literal translation from Japanese is "My body is made of swords." That's just weird though.