It is a live leech that is also used in the treatment of humans.
In fact, the body of the leech is internally divided into 32 parts and each part has its own brain, as if there were 32 brains inside the leech.
The bite of a leech is not painful or poisonous but it is beneficial to human beings to some extent, in case of infection, applying it to the body sucks out poisonous blood and saves human life.
The leech has 300 teeth and a mean age of 1 year.