Kryten is a robot aboard Red Dwarf. Kryten (pronounced: cry-ton), was programmed to do only nice things and to obey everyone until Lister taught him how to lie and how to insult people. The rough edges around Kryten's insulting problem are visible when he tries to call someone a smeghead. He can barely squeeze out the words; but if he tries to, you know he is mad. Kryten is always trying to figure out why humans do certain things or why humans feel certain things. Kryten has learned and studied and Kryten himself is very near human at heart. With lots of great memorable lines and funny remarks, Kryten is my favorite "boy from the Dwarf."
Cat evolved from over a period of 3 million years, to make a half-cat, half-human character. Cat flies the Starbug along with Lister. Cat is one of the two oxygen breathing crew members on Red Dwarf, and he is very concerned with his looks and he cares a great deal about his clothes and fashion. Cat thinks so highly of himself that I believe that he is the only person he truly loves. With stupid lines and a not-so-smart head, Cat makes for a hilarious character.
Lister is the last remaining human in the world. Lister is a pilot and in my opinion, the leader of the Red Dwarf crew. Lister hates Rimmer the most. Lister's most prized posession is his guitar. Lister is well-liked among the crew, but he doesn't get enough credit. Lister is funny and has a huge part in Red Dwarf.