In "Love is in the Blood", one of the story arcs involves the protagonists fighting against Cieba. Who/what exactly is he and what's his backstory with Laila?
The "cast" page identifies him as a Master Vampire
"Ceiba – Master vampire – Once the ruler of many Meso-American cultures over the centuries, including the Mayans and Incas. He is a powerful figure in the government of modern Mexico."
As to his back-story with Laila, She claims not to have seen him since the 1520s and says that she's been assiduously avoiding him ever since. In a later edition he says that she has "advised kings and led their armies" and that he is "seeking revenge on her and the humans" after she abandoned him precisely 10 days before the Massacre at the Main Temple during the Siege of Technochtitlan when the "Temple Mayor rained blood"
The implication is that she was working for him as an adviser, betrayed him to the Spanish (who promptly sacked his temple) and then left with them back to Europe. There's also a subtle implication that they used to be lovers.