Cat (Danny John-Jules)
Cat is the last known member of his species, felis sapiens, who evolved on Red Dwarf in the 3 million years that Lister was in stasis from Lister’s pet cat Frankenstein. Cat has no name, and is simply referred to as Cat by the rest of the crew.
Focused on his own interests, and maintaining his level of style and coolness at all times, Cat is incredibly vain, always putting himself before his companions. During his adventures on Red Dwarf it has been revealed that Cat’s greatest love is himself, and his biggest fear is becoming geeky loser version of himself, Duane Dibley.
Kryten (Robert Llewellyn)
Kryten 2X4B 532P is a Series 4000 mechanoid, who acts as something of a maid for the crew of Red Dwarf as well as their science officer. Originally the personal servant of the crew of the Nova 5, Kryten was rescued from the crashed ship by the Red Dwarf crew, where he joined them on their adventures.
Kryten is very neurotic for a robot, obsessed with cleaning and tidiness, often seen cleaning up after the crew, even in emergency situations. Through his experiences on Red Dwarf, and with the assistance of Lister, Kryten has managed to break many of his protocols and programming, becoming more of an individual.