Elf skipped work.
An Su's current identity was that of the Quasi-Saint of the Ladder Cult, which might sound impressive, but there were nine cults in the Sanctuary of Chaos, each with their own Saint Heir. He was still a full three major gradients away from Elf's rank.
After all, Elf was not only the Ladder Saintess but also the Saintess of the entire Mysticism of Chaos.
However, there were no followers present with higher status than An Su.
According to the unwritten rules of the Esoteric Sect, in the absence of a Cult's Bishop, its Saint Heir and Saintess have the right to act in the Bishop's stead. If neither the Saint Heir nor Saintess is present, then it is the Quasi-Saint Heir's turn to inherit the temporary authority.
Therefore, when An Su got rid of An Su, he became the Interim Bishop of the Ladder Cult as the mountain had no tigers, and the monkey became king.
After the coronation, An Su's whole demeanor had changed.