Blue Moon Village was a village of vampires that was founded and ruled by Sierra Mikain, bearer of the Moon Rune. Thanks to the Moon Rune's power, vampires were able to live here in peace and solitude, without having to feed on humans.
However, some 385 years ago, the Moon Rune was stolen by Neclord, a resident who had hidden his intentions. Forced to choose between feeding on humans or dying in the village, many vampires chose the latter and left. Following the loss of the Moon Rune and her home, Sierra left to destroy those vampires who chose to prey on the innocent.
After destroying Neclord and reclaiming the Moon Rune during the Dunan Unification War, it seems Sierra has no plans to return to her village.