Lieutenant Kif Kroker (born November 17, 2974) is a recurring character on Futurama. He is an undisclosed Amphibiosan alien of light green color from the planеt Amphibios 9. He is a member of the Democratic Order Of Planets (DOOP), where he acts as an assistant to the inept general Zapp Brannigan.
Though quiet and painfully bashful by nature, he loathes Zapp Brannigan and his farcical plans. He also dislikes his boss' skimpy uniforms, the contents of which are frequently revealed to the unfortunate Kif Kroker when Zapp Brannigan climbs ladders on their spaceship. This passive nature is exploited by Zapp Brannigan on several occasions, placing the blame on Kif Kroker for disastrous operations such as the Titanic's change in course, the destruction of DOOP Headquarters, and the failure to stop the invading Decapodians from taking over Earth. He is actually tired of being Zapp Brannigan's personal slave but for some unknown reason he does not even dare to say the word to his commanding officer. In fact, he does not even dare to stand up to Zapp Brannigan when he is being bullied by him. However Kif Kroker showed himself taking a stand against Zapp Brannigan by punching him hard in the stomach in The Beast With A Billion Backs and even disobeying one of Zapp Brannigan's orders in Into the Wild Green Yonder. He rarely drinks and smokes and when he is drunk he finds Zapp Brannigan's words to be extremely funny. He is timid to all beings he meets, with the exception of Philip Joshua Fry, who is assigned to be his assistant when the Planet Express Crew was drafted into the War on Spheron 1.