Human slave recently freed
Born into a robotic controlled below-ground enclave, Sterling was a slave at a young age. The super intelligent computer had long-range plans of conquering the surface and thus young Sterling was trained with guns and other technology as well as repairing and maintaining machines.
Sterling and seven other humans escaped from the enclave, but almost all of the humans perished in the harsh, unforgiving environment that is the twisted earth. Sterling was found, almost dead, by some mutants who stripped him of his advanced equipment.
While Sterling had many useful talents, the mutants of Center decided that he would be a high-class gigolo for mutants that had the money to spend. After suffering many indignities, Sterling escaped with the rest of the group after re-acquiring his possessions.