What does Tiantong do on earth?

It means a boy from heaven. The boy's reincarnation in folklore means that I was a child in a previous life, surrounded by all the immortals in Guan Gong Temple, such as serving tea and water, sweeping the floor, and serving servant girls. I was a boy all my life, and later I was reincarnated for various reasons, including remembering the past, running away, being punished for mistakes, having a special mission and so on. Past life is the reincarnation of a teenager in the sky or the reincarnation of a teenager.