It is said that Sani people lived in a beautiful place long ago - Guorao (present Kunming in Yi language), living a life of peace and contentment. Sani's chief was an honest man. He had a magic sword that helped resist invasion from other tribes: he only needed to wave his sword and recite the spell, and invaders’ heads would fall correspondingly. Even if beheaded by other people, Sani's chief could figure out a way to grow again.

Later he married a beautiful girl from another tribe. The girl defrauded his trust with sugared words and obtained his secret spell. Chief said, I would die as well as long as someone used Hedyotis diffusa to scratch my neck three times to stop my resurrection. The wife told the secret spell to the tribe chief of her maiden family, and they worked together to murder Sani Chief. Outsiders drove Sani people out of Guorao and hunted them down everywhere. Homeless Sani people escaped to Lunan Stone Forest and hid in a cave, which was soon covered by spiderwebs. Chasers rushed to the entrance of the cave only to see many spider webs. They thought it was impossible for Sani people to hide inside, so they left. No longer in danger, Sani people settled there plowing and reproducing. From then on, they have been taking spider as the god that saved their life to worship. Thus spider has become Sani people's .