Mimis are fairy-like minor spirits of Oceanykan folklore, which come in many forms, but usually have the same unpredictable personality. Their most common form is as a sort of "floating light", sometimes shaped as a being, or just as an amorphous mass. Other times they may appear as tall, elongated people.
As their moral system is different from ours, the mimi cannot be accurately gauged or measured. Folk tales say that an individual may help bring fertility to a farmer's harvest one day, and eat their child the next. A mimi may slaughter half of a travelling group, then grant riches and gifts to the remaining half. It is said that only shamans and priests understand these fairies, which makes them extremely valuable middlemen. Regular folk who try to make deals with these supernatural creatures usually end up as the protagonists of aptly named "fairy tales", which almost always end in bloodshed.
Some mimis with a more predictable personality have small, local cults dedicated to them.