Lieutenant Kif Kroker (voiced by Maurice LaMarche) is the long-suffering assistant to Captain Zapp Brannigan, consort of Amy, and Fourth Lieutenant on the Democratic Order of Planets (DOOP) starship Nimbus. Kif is a short and thin green-skinned alien from the planet Amphibios 9. His frustration with Brannigan's arrogance, general incompetence, and lack of personal boundaries in Season 1 leads him to be a disaffected, indifferent, sardonic lackey, although his personality develops through the course of the series, becoming more emotional, tender and sweet-natured later on. Zapp thinks Kif to be his best friend and loyal confidant, whereas Kif sees Brannigan as an incompetent and vain buffoon, going so far as to call him a jackass in "Love's Labours Lost in Space". Despite this, Kif seemingly has some loyalty to Brannigan, even continuing to associate with him after Brannigan caused him to be court-martialed along with him in "Brannigan, Begin Again". Kif is in a long relationship with Amy Wong, and he compares his body plan to a sea cucumber.