Onnamus is arguably the main antagonist of The Rippers. A High Priest of a cult who worships the cosmic monsters that Doctor Protheon spoke of in her video logs and drawn onto the metal of the Rippers' ship. Insane with messianic delusions, his sect spans to dozens of galaxies who seek to find one of their 'gods', even if the one they find could obliterate all existence.
- Onnamus' clothing is based on 'the King in Yellow', a character from the imaginary play within the collection of short stories under the same title written by Robert W. Chambers. Even the same symbol (the Yellow Sign) the King has is used.
- Onnamus' worship of Hastur links with Lovecraft's influence because of the book. August Derleth then written Hastur as one of the Great Old Ones who may or may not have been the King in Yellow himself.