Remoolians are a race of sapient extraterrestrial beings whose appearance is similar to a pug dog, but with four short antennae on their heads and a three-pointed tail. At least one member of this species is known to live clandestinely on Earth, disguising himself as a normal pug.
- Frank the Pug: A Remoolian living in New York City on Earth, who acted as an informant and later a full-fledged member of the MiB.
- In the episode "The Bad Seed Syndrome", Frank mentions that he has seven stomachs, but he might have been joking.
- In the alternate future seen in "The Future's So Bright Syndrome", Frank is still alive over a hundred years in the future and describes himself as 150 years old.
- Additionally, Frank's appearance in Men in Black: International proves that the lifespan of this species is longer than that of a typical Earth pug.