Who is Malcolm and Melissa from London Transports and what is their importance? London_Transports English & Literature Malcolm and Melissa | London Transports

A married couple whom everyone on a cruise to Greece hates because they are too perfect—although they do nothing obnoxious—Malcolm and Melissa six months afterward the cruise invite the anonymous narrator to their big, charming home in Holland Park for a dinner party. Malcolm runs a left-wing bookshop that makes a lot of money, while Melissa raises money for good causes. They invite the unnamed narrator to an informal dinner party that she knows will be magnificent. Melissa is happy that she will bring her friend Alice along. The narrator is concerned that both sides take a liking to one another.