I watched a Korean movie today, it was about gumihos ... so headcanon time!
(I know this picture is bad, but the google hates me and I could not find better ...)
1- Gumihos are different from kitsunes (lol, I already knew that!)
2- Gumihos has a pathological fear of tengus (just like Kitsune is afraid of dogs!) [http://ask-anilith.tumblr.com/post/109196657824/they-hide-in-the-dark-ko-tengu-vicious]
3- Gumihos are carnivorous, they eat human flesh! but mostly prefer to eat vampires and other types of undead (I also knew that already!)
4- the tails of gumiho are full of muscles and can break the back of a human being without great effort
5- the saliva of these foxy ladys is healing, if they lick a wound, them or another person, the wound heals instantly
6- Gumihos not need sex to steal souls, they only need to kiss the victim!
7- Gumihos are completely immune to poison and disease, the only thing that can make them sick is drinking the blood of another gumiho!
8- "the death kiss" is the way they have to steal the soul / life essence of a victim, usually their eyes turn green before they use the "attack" making the victim feel the worst pain in the world, even if they do not end up stealing the soul of the victim yet she will faint by acute pain
9- someone who has the soul partially devoured by a nine tailed fox, will serve her as a slave for eternity
10- the kumiho / gumiho can be both evil as good, the intentions of her vary with each person she find, but being kissed by one of them (and not having your soul eaten ) is a harbinger of good luck
11- many supernatural creatures are afraid of gumihos because they're soul stealers (the ones that do not have this fear are: dragons and tengus)
12- one Gumiho can use her tails as arms or legs
13- the eyes of Kumiho reveal the emotions of them (example: blue when they are calm and relaxed, yellow when they feel fear ....)
14- Gumihos has a supernatural intelligence, much larger than any human will ever have
15- Kumihos can not be injured by fire or lightning, and can control them, but they are totally weak against ice
16- if you plan to hold a gumiho, make sure that you've tied her tails (and at least threw them into ice water) otherwise you will not be able to hold them!
17- mistaking a gumiho with kitsune can send you to the grave much earlier than you think
// Just to complete ... AHRI is a gumiho not a kitsune, so luna is also a gumiho