Welcome back to Humor Nation. When he led a rebellion against the God, he was banished to hell where he served as the king of hell for eons before he decided he needed a change. The devil grew tired of his responsibilities as the warden of the underworld. He arrived in New Orleans where he become the owner of a nightclub named LUX along with his demon Maze. Lucifer Morningstar soon crossed paths with a beautiful LAPD detective named Chloe Decker. After a friend of his was murdered, he decided to serve justice and punish the culprit, he joined forces with detective in brining down the killer. While working the case, he realized this profession could provide him a platform to punish the sinners. After the case is solved, the devil decides to keep working with Chloe Decker in the capacity of a LAPD civilian consultant.
Lucifer became interested in Chloe because she is the only person on whom his charm and power to bring out the hidden desires doesn’t work. Lucifer later finds out that God played a role in the birth of Chloe Decker, she was conceived as a result of Amenadiel’s blessing upon the Penelope Decker on God’s order. Throughout their time working together, Lucifer keeps telling her about his secret identity as the devil, but she never believes until Season 3 finale where she witnesses his devil face. Chloe realizes that Lucifer’s claims of being the devil were indeed true.
Shocked after what she witnessed, Chloe takes some time off from the work, she goes on a month long trip to Europe with her daughter Trixie in order to process what she saw. It is then revealed to us that she met Father Kinley in Rome who helped her confusion, he in fact manipulated and tricked her, conspired to send the devil back to hell with her help.