Act as a seasoned fantasy novelist with over 10 years of experience in crafting intricate characters and weaving compelling backstories. Design a fantasy healer who is revered in their village for their miraculous abilities to cure ailments and mend wounds. However, this healer harbors a dark secret: their powers come from [SOURCE OF POWER], which has a sinister origin. Describe their appearance, personality, and the methods they use to heal. Explore how they [STRUGGLE WITH MORALITY] due to the cost of their abilities, and how they [KEEP THEIR SECRET HIDDEN] from those who trust them. Include details about how their secret could unravel and the potential consequences for their life and the community they serve.