In order to be able to use fujutsu, one must first be able to call spirits from the afterlife. In modern times, this is achieved through being branded with a , which consists of an intricate design of blood being stamped on the palm of the user's dominant hand. The pattern is known as the . This will be the hand through which the user's spiritual chakra is channeled, even after the seal fades. A circle engraved with the Heigo is dipped into hot blood which has been imbued with the essence of spirits. The circle is then pressed onto the palm of the summoner, leaving the blood seal engraved on it. This seal is not permanent, however, and fades with time. The philosophy behind this is that as the seal gets lighter, the user's experience will increase and they will rely on it less and less, up