Lucius was an un-noteworthy wealthy merchant in the city of Deeptown many years ago. His family was taken from him by pirates, killed when the ship they were passengers on was hit. After that he sunk much of his money into funding a fleet of privateers to combat the pirate threat that plagued the merchants of Pla'thos and southern Lados. He was eventually killed in his own home by those same pirates he was trying to hunt down.
For several years the mansion went unused, abandoned and oddly shunned. Then, during the occupation of Deeptown by the Sect of Sixty, his home became the site of many gruesome murders by the demon worshippers, stirring him from his rest as more and more dark magic was worked in the very place he had started his family, and where his own blood was spilled. He became a spectre then, and aided the heroes that ended the threat of the Sect of Sixty, which included Takeshitora Bladesong. That group used his home as a base of operations for a time, with Lucius's blessing, but eventually moved on. Lucius passes out of memory at this point for many years.
It is not until the Era of Heroes that he reenters the scene. After the Culling, most of Pla'thos had been destroyed, and his home was only barely spared. It had become a ruin atop of wave-threatened jagged piece of stone, but still he was tied to the place. He'd had a lot of time to explore his ghostly powers, and learned how to possess the living and manifest himself physically for a time, among other tricks. It is here in this state that he was found by Elizabeth Threnody, an explorer.
Lucius was smitten with the woman, who looked hauntingly like his late wife. The two grew close over several days of conversations, and eventually Lucius found himself no longer bound to his house, but now bound to this woman. From then on he was seen with her, when he was seen at all, as the two continued Elizabeth's missions and looked for ways to bring Lucius back into the world of the living.