Shar

The Faerûnian goddess of darkness and night, the malevolent twin counterpart to the goddess of the moon, Selûne. She was also the creator of the Shadow Weave, a dark counterpart and attack upon the Weave of Mystryl and her successors, before both of the Weaves fell into ruin during the Spellplague. The domain of The Mistress of the Night was not only that of dark places, including caverns, dungeons, and the Underdark, but of deeds done under darkness, of secrets, loss, hidden pain, and the ability to forget.
The very existence of Shar was paradoxical; the Nightbringer was brought into existence by the creation of Realmspace, but was the living embodiment of the void, the perfect nothing that existed before she was born. The emptiness that she originally reflected had itself been erased at the start of time, and she longed to return to the ancient calm of nonexistence. By her very nature, Shar was defined by loss, the foolishness of hope, and the basic principle that life was a joke.
The depths of Shar's evil were too extreme to be described in words. She was deeply twisted and perverse, a being of ceaseless, petty hate and envy. She plotted from the shadows to undermine all creation, reveling in the hidden and never to be revealed. Though she was not chaotic herself, like her sister was, Shar nonetheless sought to destroy all order. Even her own devoted worshipers were simply pawns in her overarching scheme against everything there ever was and ever would be.
Although Shar purported to be a healer, soothing the grief-stricken by letting them forget their woes, she was in truth a sadist, and enjoyed inflicting the pain of loss on her worshipers. Her alleged help was not release from that pain, but numbness to it, the acceptance of it as normal and the removal of any expectation otherwise. The Lady of Loss did not truly believe in healing grief, not even her own, but in harnessing it, in nurturing spite, nursing indignity, and reinforcing regret until minor slights, at least in her mind, become transgressions worthy of bitter vengeance.