People have previous lives and afterlife, and reincarnation continues from life to life. Samsara means circulation, which means that the human soul is constantly rotating in the world like a wheel. The place that controls reincarnation is called the "Reincarnation Pavilion", but few people know about reincarnation in the world.
However, the origin of the story is not in the Reincarnation Pavilion, but in an... Abandoned spirit.