When Northern Wei 's Emperor Daowu ( Tuoba Gui ) sought marriage with Later Qin , Yao Xing , because of this and .
Yao Xing heard that Daowu Emperor already had Empress Murong as Yao Xing 's wife .
When Northern Wei 's Emperor Daowu ( Tuoba Gui ) sought marriage with Later Qin , Yao Xing , because of this and because he heard that Emperor Daowu already had Empress Murong as his wife .