An appropriately mocking response to single men when they complain about not being able to find their ideal mate. Originated from the game Super Mario Bros. when at the end of every world save the last one Mario would be greeted by a mushroom man who would inform him "Thank you Mario! But our princess is in another castle!" And when he does finally find the Princess she just sends him out to do it all over again with more difficult challenges. Represents the futility of the search for a mate in a humorous way to which the children of the 80's can easily relate.
Single guy: So I spent another Valentine's day alone at the bar, I hate my life sometimes. Where am I suppose to find a sane girlfriend?

His not single friend: But our princess is in another castle.
by Boss79 February 17, 2009
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