Kafka is a dark, hidden organization/place that does illegal genetic research. Their ultimate goal is to bring about the growth of incuna cells in human beings. It's astounding energy would give way to the creation of diverse species from the people they brought in, evolving them into high-level human-like forms bringing them into the world. The ultimate conclusion to their experiments would be a being bringing life into its next revolutionary stage of higher existence. Giving future beings greater knowledge and strength. Having the being of the next evolution ruling as a key to the success of human evolution.
The Kafka spoke of their research to the experiments and people working in kafka as being for the sake of human success. That it was all for the sake of humanity and no one else.
They oppose the government and work against Circus. They support something they call "Evolution", which uses a certain type of cell to change bodies and makes most people lose their minds and kill people to eat. It gives them great powers, which is why so many people find it enticing, although they aren't trusted by Kafka. Kafka is suspected by the government and Circus, but no one has been able to find evidence of their activies. They always come close, but can never find proof.