Age: Tens of thousands of years
Birthday: July 7th
Appearance: Djinn are by default formless, and can choose their own appearance at will. Her height is completely variable, typically ranging from six to nine feet tall, and dressed in the finest robes her magic could conjure. When not disguising herself as a human, her eyes glow brightly and her skin tone looks somewhere between human and demon. Despite not being subject to aging, since the Demon War Sila has altered her face to reflect the passing of the years, but the lines one her face can come and go as she pleases.
Personality: Sila is one of the few beings whose insubordination Mortem will tolerate. She knows well enough not to do so in public, and remains an enigmatic figure of indeterminate role to the Demon Lord's minions and to his enemies. The conflict between humans and demons is of little concern to her, she only sees it as a means to an end to inflict mass pain and live a wealthy and powerful life with her husband. She seems to be grumpy most of the time in demeanor, but that may be due to Mortem being dead for thousands of years.
History: Sila's ring was brought to Earth in humanity's dawn in the form of a meteorite, and for many generations of humans granted wishes to those curious enough to posess it. Like many Djinn artifacts, Sila's ring traded hands many times between many powerful people, mostly archdemons, often the first introduction of many cultures to the power of magic. One selfish emporer held off on his last wish for too long and took her ring to the grave with him, sechluding her from the world, until it was found by a half-infernal named Mortem. Mortem was a curious subject. His frustration with his first two wishes going awry was typical, but his response wasn't; deciding to ask for a wish Sila wouldn't want to subvert, he wished for her freedom. Sila took it and left.
Sila wandered the Earth for a few years, wreaking havoc when she pleased, but eventually curiosity got the better of her when Mortem's reputation began growing. She joined back with him and helped him on his quest, and after a while the two fell deeply in love. Which was convenient for Mortem, considering it was this devotion that motivated Sila to carry his soul at great expense to herself throughout the millenia until the present day. After the Great Demon War the Infernals retreated to the Earth's mantle and saw their failure as a sign they never should've put their faith in Mortem to begin with, and shunned Sila from their civilization. Without access to the Inferanls, Sila was left to wander the Earth near-powerless and in hiding from Mortem's enemies in search of a naturally occuring human/infernal hybrid to put Mortem's soul in, which was a very long wait.
Skills: Charismatic and devious.
Magic: It's easier to say what Sila can't do rather than what she can do. After being freed from her ring Sila could not longer be considered truly omnipotent, but her magic still obeys many of the same limitations that her wish-granting abilities had.
You can't wish for murder. Sila posesses no magic that is easily capable of directly wounding someone, though she can get others to do it for her.
You can't wish for love. Sila is incapable of accessing or manipulating someone's mind. She cannot read minds, control minds, edit memories, or any of that sort. Her clairvoyant and general information-gathering powers are fairly limited as well.
You can't wish for more wishes. Sila can't turn anyone else into a genie, a wizard, or any other being that can create spells or manipulate magic itself. Any power-boosting that Sila grants someone is limited in duration.
You can't wish the dead back to life. Sila can't bring the dead back to life without prior preparation (as she had with Mortem).
Additionally, there are limits to the scale, distance and specificity at which Sila can perform magic (she can only stop time temporarily, for example).