Im bored. But wanted to do something productie.
Soo...im going to explain Afenens Bioluninescence.
its not magic. its chemistry.

Now Granted i am NOT a chemist or biologist. this is for fakes. not found in mammals.

Afenen posses an organ called a photophore, which produces a the chemical Luciferin. when combined with O2, the chemical lucifrase catalyzes the reaction resulting in Oxyluciferin. This causes the glow.
Now, the oxylucferin is sent through a seperate circulatory sysem (similar to lymphnodes)but closer to the skin. when it reaches its destination; The Nose, Pawpads, Eyes, nipples (anthro),toungue, horns and vulva it glows!

oh. and dont go all nerdycorrecty on me. this is IMPOSSIBLE in RL.
how can i possible know how a photophore actually works? XD

HAHAHA.
enjoy