I doubt that you manage to understand the sense of humor of the woman Sagittarius because you see life far more seriously.
And her careless attitude amazes you every time she drops something from her strong hands accidentally and starts laughing, while silently you sum up the damage she had caused. Still you can relax and enjoy the time with her, because neither of has a strong desire for commitment, and that will predetermine the close end of your relationship. She is fond of romantics while you are keen on machines. If you manage to combine these interests, my hypothesis of the close end of your relationship may not come true. As far as sex is concerned you can expect everything and nothing – again we have uncertain prognosis due to the inconstant character of your signs.