I have to admit, Sin was the one member of SENTINELS I wasn't sure what to do with. When I first created him I liked him solely for his look and his connection to Gospel. I liked the idea of a twin brother and sister who who were powered by good and evil. I liked that their father would be a ruler of Hell and I had worked out that Sin and Gospel would eventually switch looks. But beyond that, I wasn't sure what to do with him.
When I was writing SENTINELS Book 1: Footsteps, I put in a line where Gospel tells Harlette that her and Sin's fate are intertwined. It wasn't my original idea to pair them up, but I liked it and as it developed it seemed to work. It also helped to add to Sin's change and gave him more of a personality then just "I have to find my sister.".
Another thing that eventually helped me to really like his character was Luciano's visuals for him. When I first saw his ideas for Sin for Book 2, I was blown away. It finally all became clear to me what he was about. And as we developed him in Books 3 and 4, I think he really grew into his own. Plus I loved the light wings, lol.
Another cool thing that wasn't planned was Harlette and Sin's twins. I originally saw them as having a son, but it was Luciano's idea that they have twins and it made perfect sense. It also gave Sin more depth in that he was now truly following in his father's footsteps.
I had asked Luciano to write one of the story for the SENTINELS Anthology and to my surprise, he asked to write Sin. Luciano had grown a lot as a creator and I knew he could tackle Sin's story really well. I joked that I should draw his story and it would be a cool change of roles for us.
I had no idea what I was getting myself into!