Saintess of Hehuan Sect did not immediately agree to Ji Changsheng's request.
Instead, she continued to tempt Ji Changsheng:
"Are you sure? My promise is to grant you one request, and you're making such a simple one? You should know that even if you want me, I could agree to it."
If I believed a single word you said, then I might as well be Li Daoyan, Ji Changsheng thought.
As if I'm some cheap, gullible fool.
When someone in power suggests that you can make any request, you need to understand that they're just being polite, not that you can really ask for anything and everything.
The moment you take it seriously, you'll quickly learn of that person's quick-change act from gracious to harsh.
Besides, the gap in their cultivation base was too vast.
Even if he truly dual-cultivated with the Saintess of Hehuan Sect now, Ji Changsheng worries he might end up drained of his yang energy to restore her yin energy.