Human

Humans are an extinct animal species that once populated the world 12,000 years ago, before the start of the Mollusc Era. It is stated that the rising sea levels caused the extinction. Many remaining artifacts from the humans are still present and discovered by the current inhabitants, such as Inklings. Human fossils and bones have been found and are exhibited in museums.

Currently, the only specific human being that is known is the "professor", which created Commander Tartar, an AI designed to pass down humanity's knowledge to the next evolved life. There is also another human that is implied to be Judd's pevious owner, where the human cryogenetically sealed Judd in a machine to preserve him for the future. The machine is also capable of creating a clone of Judd, as the human feared that the cat would be lonely. Since both humans are seen as scientists, it is possible that the professor and Judd's owner are the same person.

Trivia

 * In the dialogue for Shellendorf Institute, Pearl mentions that she has dug up human bones before, to which Marina replies that they are found everywhere.
 * The first artbook features comic of an early version of background story, where the extinction was caused by humans accidently droping a nuclear bomb in Antarctica, which worsened the already rising sea levels.
 * In the first artbook, it is implied that humans created the domes found in Octo Valley as a place to flee during the flooding.
 * The NILS Statue resembles a giant human being.