With them holding each other in check, no one could act without restraint. This was the only arrangement that met his requirements.
He had no desire to see the Pill Pavilion descend into a corrupt mess.
When a single faction controls a place, it's easy for them to collude and create all sorts of problems. In contrast, a three-way balance of power would act as a check, preventing things from developing in too negative a direction.
Since Yang Chan represented the Merak Saintess, Bai Keyi, as the Pavilion Master of the Pill Pavilion, had a very clear choice.
"If the Pavilion Master says so, I have no objections!"
"Same here!"
As soon as the Pavilion Master spoke, the two Vice Pavilion Masters, who hadn't been paying much attention to the matter, quickly voiced their agreement.
