King Lir is an ancient Erathi king who resided in what is now known as The Blackened Hall, on the Tywili Coast, with his two sons and wife Aife. As the legend goes, King Lir was a great ruler, beloved by his people and servants, but darkness fell upon his reign and his family when he married Aife. Aife was a Niskaru demon in disguise, and over time, she eventually unraveled his kingdom and destroyed everyone in The Blackened Hall.
According to Scribe Pearse, a servant who kept vigilant journals, at a certain point, after the deaths of his sons, Lir confined himself to his room and his wife refused anyone servant to enter. At some point down the line, Aife finally revealed herself as an unkillable demon, and it is presumable that Lir had been dead or ailing at her hands for some time before the court discovered his demise.
May have been inspired by the tale of Briton King Leir (better known by his Shakespearean counterpart, King Lear), who was betrayed by two of his daughters due to their thirst for power and his kingdom.
More likely, Aife and Lir's tale most certainly comes from the Irish legend "Children of Lir", in which Aife was the second wife to Lir, and, jealous of his children, had them turned into swans, and in turn, she was turned into a demon. Interestingly enough, the tale also makes mention of a people known as Tuatha Dé Danann.