Crystal was a female Venusian exotic dancer who Dave Lister was married to in an alternate reality. As a pet name, Lister called her either "Crissy" or "Krissy". The character was unseen and mentioned only.
History
Arnold Rimmer once got hold of a Quantum Skipper and used it to explore The Multiverse. Eventually he found a dimension where his former bunkmate and subordinate Dave Lister was instead the captain of Red Dwarf. In this dimension, the Cadmium II radiation leak had never occurred, and Red Dwarf had never left Earth's Solar System. This was because Lister had noticed the faulty drive plate before the accident had happened; instead of accepting a pay-off, Lister instead opted for shares in the JMC, making a fortune when a planet rich in Helium-7 was discovered.
When Rimmer tried explaining to Lister that he was exploring The Multiverse, Lister believed that he was referring to a strip club on Venus called "The Multiverse", and denied ever being there, before admitting that he is a lifetime member.
Lister was also happily married to "Krissy", who Rimmer initially believed to be Kristine Kochanski whom Lister had been in love with in his own dimension. However, captain Lister's wife was actually Crystal, a stripper who Lister had met at The Multiverse, when she danced at table nine.
Rimmer was extremely jealous that Lister was married to a stripper, was rich and a ship captain, and could not stand to remain in a dimension where Lister was more successful than him, and ultimately returned to his own dimension. ("Skipper", Series XII)
Trivia
- It is unknown if Crystal was her real name, since it may have been her exotic dancer name. It is possible that it was her real name however (or at least something similar), since Lister calls her by a what may be a shortened version of it. It is unknown if she took her husband's surname either.
- The alternate Lister never mentions that he has any children, only that he is looking forward to getting home and seeing Krissy. It is therefore unknown whether Jim and Bexley Lister exist in this dimension.
- Given that Lister was very wealthy in this dimension, and given the circumstances of their meeting, it is possible that Crystal fit the stereotype of a "trophy wife" and a "gold digger".