He was the first sapient being she met after being harrassed by God’s angels after she left the Garden. She thought he, too, had been sent to harass her, in fact. Could anyone blame her? He was radiant, like the last visible star in the pale colours of dawn, with far too many wings, far too little clothing, and a massive snake around his alabaster shoulders.
Looking back, the fact that he was walking, and not flying, floating, or otherwise acting like gravity had no sway upon him, should have been her first clue that he was not Heaven-sent.
Her first clue at the time was that when she cursed him with the True Name, he didn’t even flinch.
The second was that when she repeated she would never return to the Garden, he replied that neither would he.
When she responded somewhat sarcastically by saying that they would get along wonderfully, then, the not-angel had agreed with a grin that was only partly sincere.
And yet, they did.
Unlike Adam, a curse be upon his house, Lucifer never demanded to be served, or that Lilith lied beneath. In fact, he gladly lied beneath for Lilith, who was the first to introduce him to carnal pleasure. Lilith would never forget that angelic face contorted in ecstasy and that golden hair spilled on the barren soil. Neither would she forget the perfectly wanton look in his golden eyes after the act, betraying his discovery of a bottomless hunger within himself.
And yet, he never demanded the exclusive right to her body that she would have refused him.
But from that day on, whenever Lilith came to him, of her own free will, he smiled, and lied beneath.