Moromnus is a weekee rebel, one of the villains of Tintin in Tokyo. Following the trend of Latin based names for Weekee characters, his name comes from Mors Mortis, the Latin word for death, and Omnis, the Latin word for all.

He replaced Malimors, but was rivaled by Navelan. Navelan and Moromnus came to open blows over the possession of Tintin. Unfortunately for them, Tintin was saved by Gamera. He and his allies used Weekee puppets on earth.