A silent humanoid species found living inside the starless Void in 2377, treated as vermin by the trapped ships there until the Doctor learned to communicate with them through music.
The Void is a pocket of empty space from which no ship can easily escape, and the vessels pulled into it survive by raiding each other. Among them lives a hairless, pale species that stows away on ships and scavenges supplies. Their origins are unknown, and the other crews hunt them as pests.
In the episode The Void, Voyager finds one hiding aboard. Janeway shelters him and the Doctor names him Fantome. He cannot or does not speak, but responds strongly to music, and the Doctor builds a language of tones that lets them converse. Others of his kind are later taken in.
When Janeway's alliance of ships attempts to break out, Fantome and his companions slip aboard the hostile vessels that try to stop them and disable their engines. They choose to stay behind in the Void, which they regard as home.