The Vessel

Because the leader of the bahro ("the Sovereign") can live such a long time, it became traditional for her essence to be downloaded into a sacred vessel, dubbed 'the Egg' by the humans.

The Sovereign is meant to spend time in this vessel prior to being transferred into the body of the Protector, a bahro who serves as leader during the Sovereign's incubation, and who sacrifices her body during the rite of Transmigration when it comes time for the Sovereign to emerge.