The Slithergee were a race of obsequious alien slugs whose home planet was destroyed.
Slithergees were blind creatures and hunted their prey by scent. Slithergees also used slaves as sight guides and had a fear of darkness.
A spacecraft carrying the Slithergee arrived in the orbit of the colony planet Puxatornee, requesting the permission to settle on the first moon. Otherwise, they would humbly threaten to declare all-out war. Interference from alternate futures — unwillingly aided by the Seventh Doctor — resulted in the creation of two timelines branching out from this event, with one timeline seeing a war being waged between the Slithergee and the human colonists that reduced Puxatornee to a radioactive cinder and the other seeing a policy of appeasement towards the Slithergee going so far that the Slithergee took complete control of the colony and prosecuted human objections as "hate crimes". (AUDIO: Flip-Flop)
A Slithergee ice dance spectacular show was being held at the Sirius Exhibition Station when the Eighth Doctor and Lucie Miller visited. (AUDIO: Max Warp)
During Lucie Miller's travels with the Monk, she attended the final of Thordon's Got Talent, which was won by a singing Slithergee. (AUDIO: The Resurrection of Mars)
Bernice Summerfield considered "Slithergee silverware" to be something Irving Braxiatel would want to obtain for the Braxiatel Collection. (PROSE: There Never Need Be Longing In Your Eyes)
As they had the ability to exude guilt and pity, the Slithergee often worked in the hospitality sector. Orval Ignashus, a Slithergee, worked as manager of the Galileo Spotel. When the trillionaire Berkley Silver was assassinated in his Penthouse Suite, Ignashus had no choice but to put the spotel into lockdown as per galactic protocol. (AUDIO: The Memory Box)
River Song thought she recognised Slithergee architecture in the buildings generated by the ruins of a prototype TARDIS. (AUDIO: Lies in Ruins)