In the venue of the banquet, the eyes of many saw Bai Luli off.
As he said it himself, he was no saint and, therefore, was imperfect. As such, he would have been angered and would have resented people and things. As he put it himself, he was unable to forgive Zhuge Mingyue and Gu Dongliu, yet that battle changed his mind and he calmed down. It was probably done out of respect and acknowledgment for Gu Dongliu's prowess and belief, but Bai Luli looked even more human for doing so.
Bai Luli was, after all, the number one genius in all of Barren State and the heir chosen by the Holy Zhi Palace. As such, his temperament would have been that with a comprehensive moral compass. Bai Luli was a person worthy of respect and so was Gu Dongliu. Gu Dongliu would probably be yet another Bai Luli, and everyone in the Barren State would learn his name after that battle.
