Sango notices that InuYasha, Kagome, Shippo, and Miroku had helped buried the graves of her fellow villagers. She uncovers the secret to passing through the barrier to a cave near her village where the shrine maiden Midoriko created the Shikon Jewel, able to purify the souls of the yōkai. It is explained when a person contains the four spirits, being courage, friendship, wisdom, and love, at their maximum, they unite to form a really strong and powerful balance within the soul that can be used for either good or evil.