Anyone feel like doing a shader?

Looking for something that overlays the colored(non-black or non-transparent) part of skin2 over skin1 to create self-illumination glowing parts.

I have no idea the level of difficulty so I understand if this work than worth doing quick and dirty for fun.

Thank you for your time.
Mal

EDIT- Looking for image examples, will add soon.




Actual light cast not required but would be nice.

Thank you
Mal