Firefly does not have subsurface scattering at the moment. Sad but true. There are some threads about real skin shaders here and at RDNA, BagginsBill has written a lot about this.

I use face_off's real skin shader script here from the marketplace for most of my figures, but there are free ones - for example BagginsBills unbelievable complicated Apollo Skin Shader. www.runtimedna.com/mod/forum/messages.php

If you want reals SSS, you should use a different software for rendering. Vue has SSS, for example.

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

Avatar image of me done by Chidori.