A type of undead that wanders through graveyards, desert regions, etc. They were also called “shokujinki” (man-eating demon) during the age of the former demon lord. What they preferred was to eat raw human flesh. They were fearsome monsters. Of course, in the present, they don't eat human flesh, but their nature remains intact even now that they've switched to consuming human spirit energy through semen as their main food. Their personalities are extremely ferocious just as in the age of the former Demon Lord's and they attack human men ravenously in pursuit of food.
They were once “shokujinki,” they mainly use their mouths -which was once used to hungrily devour people- to milk semen from human men. They open their mouth wide as if devouring prey and stuff their cheeks with a man's penis. They purse their lips, licking and sucking with their tongue moving relentlessly in all directions. The pleasure they give to a man makes him feel as if he's going to melt and be digested. Their mouth is like the vagina in other monsters and the inside of the tepid orifice pulses along with the penis. It's an exquisite semen sucking organ that can freely change shape to provide various stimulation to milk a penis. When a man releases their favourite treat and it nearly overflows, they noisily gulp down every last drop.
It seems that they can't stay calm unless they have something to put in their mouths. If the man they fancy leaves himself vulnerable, they'll probably try to suck on his penis. Even at other times when they're not having sex, they like to lick and suck on a man's fingers, ears, toes, etc. anywhere on a man's body. Their saliva contains a digestive compound, or rather, a compound that causes a person to become extremely sensitive to pleasure, it takes effect whenever they put their mouth on any part of a man's body.
For that reason, even if it's not his penis, having any part of his body sucked by them will cause a man to be overcome with intense pleasure, just like having his penis sucked. Also nibbling the skin in that state, causes pleasure to course throughout the entire male body, almost like an electrical shock. To ghouls, nibbling a man is the greatest expression of affection. When they leave teeth marks on a man's skin, it's proof that the man is theirs, this reaffirms that they've obtained a dear husband. They'll smile alluringly and then go for the penis and suck it to reconfirm their love.
Additionally, to them, their vagina is an extremely sensitive weak point. Since their mouth fills the role of a sex organ, they ordinarily don't use their vagina. Since their vagina has never known pleasure, it is several times more sensitive than that of other monsters. It is said that if a man shoves his penis in there, it will cause them to be overwhelmed with so much pleasure that they nearly pass out. They won't be able to concentrate on milking semen when every stroke of the penis attacks them with enough pleasure to nearly drive them mad. Once their body learns of vaginal pleasure in this manner, what they consider to be their lower mouth becomes an organ for licking and sucking the penis, just the same as their upper mouth.
They are called "Shishokuki" (corpse-eating demon) as well. As the name suggests, when they sense the smell of a woman's corpse that has been freshly buried, they dig it up and then give her a portion of their demonic energy, thus reviving the woman as one of their own kind, a ghoul. The woman then becomes a ghoul in body and heart, being newly reborn, she'll be overcome by an intense hunger, rendering her unable to think of anything else but using her mouth to suck off a man to quench her dry throat using his semen.