倾国倾城不及倾你一人
[qīng guó qīng chéng bù jí qīng nĭ yī rén]
The phrase means 'Even someone as beautiful as to have the nation and city 'fall in love' can't compare to loving you alone'. It comes from an ancient Chinese praise for exceptional feminine beauty, extended here into devotion to a single person, signifying how no one else can ever match this one special individual.