The lack of physical substance would therefore seem to be a defining characteristic of an intangible asset. Both the IASB and FASB definitions specifically preclude monetary assets in their definition of an intangible asset.
Leeches are segmented worms in the Subclass Hirudinea that are usually ectoparasitic. They belong to the Class Clitellata (along with earthworms, Subclass Oligochaeta) because of the presence of a clitellum, which is a swelling towards the head of the animal, where the gonads are located.
Leeches are also in the phylum Annelida. Most leeches live in water and have suckers at both ends of their bodies. The tail suckers are used to latch on to a host, while the head suckers are used to suck blood from the host. Most leeches are predators or scavengers, but some suck blood.