What is a japanese back tattoo called?

The traditional Japanese full back tattoo starts at the shoulders, and extends across the buttocks to terminate at the mid thigh. The Japanese back tattoo is called “kame no ko” which means “shell of the turtle”. The implication is as strong as it is clear. The wearer is both embellished and protected by the beautiful shell that he wears.

Nukibori Orochi to Dokoro, on Mrs H, 2022-2023