A little Mentalism Lecture

...…

It was already afternoon when Shin was finally able to move his body without having much pain while moving. And the pain didn't come from his bones, but from his veins, muscles and tendons.

"D*mn! It is f*cking hurts," cursed Shin as he tried to stand up for his bed and stretched his body.

Then he added a little later. "I know that it is going to be like this since it was mentioned in the manual of the 'Reinforce Iron Bones', but I didn't say that it is going to be this way. What's worst, it is also written that this is going to last for four days."

While he was complaining, an aged voice suddenly interrupted him (once again). "That is because your body is adjusting to your new set of bones. With that, your bone marrow was producing a new set of your blood; and with strengthened blood cells at that."