Isn't it similar with women, the one and done principle? One who remains attractive forever with lots of sex appeal, who can cook well, is a caring mother, pursues her own career, always spoils her husband with little loving attentions, shares or admires his hobbies, is faithfully intelligent and full of esprit, with whom you can have lively conversations about very interesting topics, with lots of pros and cons but without being argumentative, that never gets boring and who has a very sympathetic mother because she will be your mother-in-law for a very long time.
Obviously there are lots of women like that, but where will they be able to find their 'one and done' men?
