Glass Cow

Glass Cow acquired her name from her unnatural property of being translucent. The origin of this ability is a cautionary tale that begins with a magical monkey's paw, which she found in a shady corner of her farm. Upon realising that she would be granted 5 wishes, she thought up the first desire to be invisible. Despite her intention being to escape the farm she belonged to, her unfortunate use of the very specific term "translucent" prompted the monkey's paw to apply an effect resembling glass. While possible to see objects through her, anybody with reasonable visual acuity is able to make out her shape from the distortion of light and will therefore be aware of her presence. Her explanation for the mistake reveals that English is actually her second language, with her primary being the cow language native to her species. Glass Cow has gone on record expressing "that asshole knew exactly what I meant".

In a remarkably less ironic twist, the monkey's paw also scrambled away on its fingers, laughing and not allowing her to redeem any of the remaining 4 wishes. This action is considered to be extremely dishonourable among monkey's paws, and this particular entity has never resurfaced since, likely due to fear of punishment by the council of elder monkey's paws or perhaps legal action taken by Glass Cow.

In Cow Review
Glass Cow was featured on Cow Review in season 1 episode 10, with Josh presenting a more wonderous outlook than usual, proposing such interesting concepts as: She earned a rating of 7/10 cows, with Josh giving such reasons as:
 * Whether this cow made entirely of glass or if it has activated active camouflage from the Halo franchise.
 * What this cow gets up to with its see through abilities.
 * Whether its milk still comes out as white or instead is also made of a translucent material.
 * This is a really cool cow.
 * If he was this cow he would creep into the female cow barn and check out some glorious udders.

Trivia

 * Despite Josh's verdict implying that creeping on female cows would be a benefit exclusive to semi-transparent entities, turning into any female cow would allow you to achieve this perverted fantasy undetected.
 * Glass Cow had supposedly planned her second wish in advance, which was going to be for youth. She is now glad she never got the chance, stating that "he probably would have pulled some Benjamin Button crap".