The mushroom in its belly pouch mentally controls Parasey's host body, keeping it docile by inducing a constant state of happy contentment in its brain chemistry. Whether this is symbiosis or parasitism is heavily discussed.
Even one bite of the mushroom carried in the pouch of a Parasey will send a person or Pokémon into a euphoric state of happiness. The Parasey will protect the mushroom with its life, allowing the mushroom to escape to begin the life cycle again.
If it senses sadness with its fluffy fur, a Parasey will rush over to the sad person, however far away, to share an egg of happiness that brings a smile to any face. Parasey are known to infest the roots of large trees en masse and drain nutrients.
