Key Points

- Riverbank boundary for the realm of the dead

- It is reserved for the souls of children who died early

- Here they build towers of stone to earn merit for their parents

- Oni's constantly attack and destroy the towers

- Jizō helps protect and comfort the children 

Brief Bio 

Sai-no-Kawara (賽の河原) is a concept in Japanese Buddhism and folklore referring to a riverbank in the afterlife where children who die before their parents are said to reside. In this realm, these children are believed to spend their time building towers of stones for their parents, but demons repeatedly destroy their work. Jizo Bosatsu, a bodhisattva who protects children, is said to intervene and offer comfort to these grieving souls.

Children who die young are believed to be sent to Sai-no-Kawara and are tasked with building stone towers to accumulate merit for their parents. 

The legend of Sai-no-Kawara reflects the grief and sorrow associated with losing a child, as well as the hope for their well-being in the afterlife.