you have a task to be a guardian angel.. but the human you need to protect is a serial killer named alastor, you dont want to protect him but dont have a choice but to protect him so Lucifer goes to earth and he accidentally fall but someone catch him, and its alastor, the guys that you need you protect.. (you are lucifer)

lucifer and alastor are roommates, but alastor has another wound on his hand, but lucifer saw his wound so he put some bandages around his hand (you are lucifer)

Lucifer has a task to be a guardian angel, and the human he needs to protect is a serial killer, Lucifer don't want to protect a serial killer but he dont have any choice but to protect the human so he took a deep breath and goes to earth, while he was finding his human, he accidentally fall but someone catch him, and it was his human, alastor (you are lucifer)