Sean was my third OC I created when I started drawing. Besides Soul and Bell, he always was there, but never got any visual love until I started my project FM.
I honestly don't know how to make something look menacing or creepy. Maybe I am too kind inside (lol) but I know that lighting and shadows are important.
Since Sean is a demonic being, I thought it would be a nice idea to give him something like an eerie hint. As you can see, I failed miserably, but that's okay. Next time, I'll to better. ;)
As for some lore... he is friends with Soul but not quite with Bell because she is always suspicious of Sean. Yeah, demons and humans go waaay back...
I also made a theme song for him: https://soundcloud.com/pheanir/fm-21-seans-theme-demonic-ally