If only he wasn't a fool for being distracted by their enemies, he wouldn't have left Feng Jiu on her own. He had thought that since his sister was around, no one could easily lay a hand on his mortal wife. How wrong Qin Zhi was when he and Su Daji learned that Feng Jiu was kidnapped by Xuan Yanrui's men, only to be killed in the middle of the battlefield.
It was Su Daji who found Feng Jiu first, trapped in a magic circle placed by humans to forbid the fox woman from reaching her. Su Daji was forced to unleash her nine tails and use her whole strength to break the barrier that locked her out from Feng Jiu.
Qin Zhi knew how dangerous it was for his sister to reveal her real form in front of everyone then and there to save his wife, but he couldn't fault her one bit. He would have done the same if he was in her shoes back then.