There was no character named Nigel...
The main characters are:
Rick: a fanatical disciple of Cliff Richard, eager to protest his lack of virginity at every opportunity.
Vyvyan: a total nutter, hell bent on bringing about maximum mayhem and destruction.
Neil: a hippy type who does most of the cooking (mainly with lentils) and cleaning (what there is of it).
Mike: a smoothie, totally out of step with the rest of the no-hope loonies in the house.
Here are some episode guides:
Series 1/
Series 2
If you haven't seen the show, you don't know what you are missing. It really is one of the funniest bits of English t.v. programming since Monty Python.