夫 「Fū 」 means Husband and 妻 「Qī 」 means Wife.
夫妻宫 「Fū Qī Gōng 」 indicates one's marital bliss, spouse's looks and
personality, whether one's spouse is more of an 'asset' or 'liability'.
Separation, divorce, or death of one's spouse can also be deduced from here.
Chinese believe that one's affinity with his/her spouse has something
to do with karma, which is why the saying, "Beauty lies in the eyes of
the beholder". A deep affinity will make a marriage last longer whereas
casual affinity will result in a premature separation or divorce.
One will be able to find the explanation in his/her 夫妻宫.
Note: In ancient China, couples were matchmade and saw each other for
the first time (usually) on their wedding day. So I'm not too sure whether
the accuracy is there by using 夫妻宫 to analyse steady relationships or lovers.