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He had one eccentricity; after our first time, in my apartment, he insisted on getting a motel room for each assignation. 'Maureen; he explained, 'if you are willing to make the effort to come where I am, then I know that you really want to. And vice versa, if I go out and rent a motel room, you know that I am interested enough to make an effort: When either of us stops making an effort, it is time to kiss and part, with no tears.'

-Heinlein, To Sail Beyond the Sunset