The Pillar of Cephiro is the person who constantly prays for peace and the well-being of all people of Cephiro. They are both a literal and figurative support for the land. Because they have to pray for Cephiro, they are not allowed to think of anything else. Thus, it becomes a problem if the Pillar happens to fall in love, for example.
After a Pillar dies, a successor is to be selected. A candidate does not necessarily have to be from Cephiro to gain the role. They can be from another world altogether and yet still be a candidate. Generally, one with a strong will is tested for the position. The means of this testing differ between the anime and the manga.
In the manga, anyone who wants to become the Pillar must first find the Road to the Pillar, which will only open to those worthy of becoming the Pillar. Upon finding the Road, the candidate must pass down the Road and undergo a test. Anyone who fails the test will disappear, but whoever passes it will become the Pillar.
If one survives entering the room holding the Proof of the Pillar, it usually means that they are the one chosen to be the new Pillar. However, this is not always the case, as with Eagle Vision. After being selected, the Proof will transform to match the new Pillar's personality.
The Pillar cannot end their own life neither can anyone from Cephiro kill them. Only the legendary Magic Knights from another world can do this.
Since Hikaru's abolishment of the system, there are to be no more Pillars.
Known Pillars of Cephiro: