Okay so When Corey killed him and he got sent to hell she was fifteen, he was eighteen He came back when she was eighteen, so he was 21 So he spent a good amount of time in hell, with other demons One of them being an old man who lost his son in a fire, he died in that same fire and went to hell, though his son didnt His sons name was austin, and also had messy black hair Since he died searching for his son he wandered everywhere in hell, also searching for his son Well when he stumbled upon Ricky he automatically thought he was his son and called him austin Ricky felt really bad after hearing what had happened to his son so he allowed him to call him that, eventually Everyone just called him that And when he came back to earth he just kept it, he felt as though it kept him from the sins of himself So yeah, I know it's confusing but there ya are