what are their flaws ? :v
Fuck I forgot to write that. They probably don’t survive long in the wild bc they’re easy to see, and they likely have some chemical imbalances bc of the glow
I love the idea of fluffies with bioluminescence!
Other fluffies might view them as a “dawk time scawy munsteh”
That’s definitely a good point. Most fluffies probably are at least slightly intimidated by them
You can’t choose them to be their owner, they choose you.
That’s another good idea. Some sort of generic quirk causes them to be skiddish and pretty much terrified of anything
ill take four
If ever some are feral wont survive with that making them like a sore thumb at night. 
I’ve done “diseases” for various fluffies, and this reminds me of a fluffy “disease” I’ve made for someone. If I may for this:
Siren’s Shimmer Virus
A odd disease that affected Unicorns and Alicorns around Japan and China, Fluffies that bear the Siren’s Shimmer Virus are fluffies that bear a bioluminescence gene inside their bodies, primarily within the affected fluffy’s bloodstream, leading to a shimmering “vein-like” design onto these fluffies, with secondary locations around either their hoofs or horns. As a result of their odd design, these sickened fluffies were given a “unofficial” nickname of Pandora Fluffies, where the disease’s name comes from. Due to the heightened energy output across a fluffy’s body due to this state, Siren’s Shimmer Fluffies bear a damaged mind that prevents them from going into a “Smarty” state, but makes their bodies incapable of camouflage with the light shimmering across their bodies. Officers in Japan and especially China bear a strong fondness for Siren’s Shimmer fluffies, using them as nightlight guides during the dark nights while working, or as valuable gifts overseas, rivalling that of regular alicorns in terms of value.
Pandora’s Sorry Box.
I had to say it.
Oh that’s cool! It would explain the existence of the trait really well