Due to its relationship with the Hollow Ancestor, the City Lord's Mansion enjoyed a transcendent status and was the most difficult organization to join.
If one wished to become a member, they had to sign a stringent Devil Contract, swearing eternal loyalty to the Hollow Ancestor and effectively becoming his subordinates for the rest of their lives.
Among the other three major organizations, the Destruction Cult and the Primordial Sin Temple were far easier to become a member of.
The Destruction Cult believed that destruction was the inevitable end of all things and thus sought to hasten the process.
As long as one wreaked havoc in the Demon World and other worlds, they would obtain the qualifications to join it.
As for the Primordial Sin Temple, the requirements for joining were more normal.
All it took was for one to complete the mission assigned to them, while showing their extraordinary characteristics.
