Glühenvolk

A Glühenvolk (GLOO-in-folk; Germ. Glühen "glow" + Volk "people") is an alien-like Wesen that appeared in. They are extremely rare humanoid reptilian creatures with magnificent glowing skin, giving them a very extraterrestrial-like appearance in recent times.

Two Glühenvolk, Vincent and his wife Jocelyn, are traveling from Nebraska to Alaska, where there are more Glühenvolk. Vincent is mutilating cows for their ovaries to feed to Jocelyn, who is very pregnant. Along their journey to Alaska, they are being hunted by a Raub-Kondor for their luminescent skins, forcing them to constantly hide in abandoned buildings, including a barn and an old cabin. While Vincent is on his way back from hunting, Jocelyn is going into labor with Nick Burkhardt, Rosalee Calvert, and Monroe helping her. After giving birth to a baby girl and the death of the hunter at Nick's hand, the Glühenvolk family continue their journey to Alaska, to meet up with the small enclave of Glühenvolk.

History
They are a very ancient Wesen species whose roots can be traced back to Africa. In the past their magnificent skin was thought to have magical properties, and today is simply valued for its beauty. Consequently they have been hunted to near extinction, and are considered as such by most other Wesen. Due to their rarity and beauty, many Wesen consider seeing a Glühenvolk to be good luck. In modern times, sightings of Glühenvolk have led humans to believe in the existence of extraterrestrials and they are of particular interest to ufologists.

Characteristics
When they woge, Glühenvolk gain bulbous heads with a barely visible nose and ears. Their mouths are filled with yellow peg-like fangs. Most notably, Glühenvolk gain reptilian bio-luminescent skin that glows a gentle, yet brilliant electric blue. The bioluminescence of these creatures is caused by luciferase, a class of enzymes found in many organisms like fireflies and many marine invertebrates. Their eyes also turn the same shade of blue, but do not glow. Their infants are born woged.

As the pregnancy advances, the female Glühenvolk needs to consume a greater quantity of cow ovaries to prevent the premature delivery of the child. During the third trimester, the female is no longer mobile enough to endure the physical nature of the hunt. During this time, the male Glühenvolk will harvest the ovaries for his mate during the night, under the cover of darkness.

They appear to be somewhat stronger than humans, as Vincent was able to rip cow ovaries out with his bare hands. They are also fast creatures, and posses great stamina.

Behavior
Glühenvolk are a benevolent species; they do not like to kill accidentally or intentionally. Male Glühenvolk are extremely caring and protective of their mates especially if their mate is pregnant. Attempting to harm a Glühenvolk's mate is one of the only ways to elicit a violent response from them. When a female Glühenvolk is pregnant, she must consume cow ovaries to stay healthy. Due to their disdain for violence, Glühenvolk prefer to attack the cows while they are asleep to lessen the rush of adrenaline, and thus, souring the flavor and texture of the meat.

Excerpt from Grimm Diaries
Thought to be extinct, Glühenvolk were considered valuable for their skin's luminescent quality and were hoarded by collectors.

It was thought to be extremely good luck to see a Glühenvolk in the wild.

Their existence and the likelihood of seeing one, was akin to the legend of the leprechaun.

''I tracked this beautiful creature to the ends of the earth. It took nearly a lifetime, but it was worth it. His skin so radiant and valuable, I poached him and retired on the fortune I made.''

A close view of Glühenvolk skin, which glows like the moon.

Trivia

 * Vincent and Jocelyn's baby was the first woged baby seen on the show.