Sin is my sona. I haven't updated her age on this ref sheet yet, but her age reflects mine so she's currently 31.
Her colors and form change based on her mood, similar to a mood ring. She also has more physical forms she takes on as disguises when she's visiting other worlds/universes.

In her base form, she's basically ectoplasm in a way as she's a more solid soul slime.

I also draw her disguises as a separate character from my sona. The best way to tell if a particular Sin is meant to be my sona is if she is wearing her star bell on her collar: My sona ALWAYS wears her star bell.

Sinnamon (C) me
Enzie (C) Ensayne
Jack (C) BaldDumboRat/Jitterbugjive
This ref sheet also features me fiance Ensayne (Enzie) and my brother Jack.