Being the leader of the Spirit Lotus Sect, Chen Wuji had a great mind and some high-level tolerance for the antics of the other sect leaders present at the table. He knew they were quirky and a handful in their own way.
San Ji was a brute who thought with his muscles and ego; if he found someone worth fighting, he would fight with them whether they liked it or not. He himself had been challenged by him a lot.
But using his mind, he would deflect San Ji's attention from the fight and direct it somewhere else.
Then there was Quiyan Yu, the silent-looking old man with the benevolent air about him. Take your eyes off him, and you will see his true nature. The lecher who is allegedly known for spying on his own sect disciples' bathings.
And worst of all… he does not spy on women.
The disciples feared to bathe in public baths, and some of them had gotten used to living without bathing.