[Where he's from, the cultivation world would certainly have expected Grandmaster Chu to whip someone for suggesting thaty demonic cultivation could be usable. It seemed on brand for the man who was vocal...often violently so, about things he didn't agree with. And what part of the famed Beidou Immortal, who seemed to stand above others seemed like the kind of person who would approve of demonic cultivation?

But while he did scowl, in truth...he was more concerned than anything.]

...I will not deny that resentful energy may be useful. But it's different from spiritual energy which comes from the self. How much can you trust that sort of cultivation? What are the potential damages to yourself?