Just like ogres and so on, these are a kind of monster called "oni".
They have the same curious features found in other oni, but the horns on their head and their fluffy, big arms and legs are soft like a plush toy stuffed full of cotton. No matter the region there is a common story that is told by parents to children, "if you don't stop crying, an oni's gonna come kidnap you", but these girls are actually the source of such oral traditions, being said to appear before children who can't stop crying or those with deep sadness even in the absence of tears. Upon spotting male prey that fits such criteria, they embrace their target tightly in their big, soft arms.
That gentle, warm embrace has the power to alleviate the target's anxiety, nervousness, fear, and the like, so no matter how stubborn the male may be, once hugged in those arms, he will want to indulge in her affection like an honest child, spontaneously entrusting himself to her soft body. And once their prey is rendered powerless in this manner, they start relentlessly soothing, consoling, and so on, until the prey stops crying and his sadness is healed. Sometimes, as part of that process, they take their prey back to their lair, which is what probably gave rise to the traditional stories. Also, due to either the charm of their devilish nature or the nature of males, for the most part, those hugged by them will seek their body, be it consciously or unconsciously. On that occasion, the Bogey will not hesitate to try and use their own body to console a male.
Given the level of devotion they'll likely show, it's practically as if their own arms, mouth, and dick-engulfing vagina exist expressly to soothe and comfort you. And once the prey's sadness heals, this time they spoil their prey, giving in to his every desire as if to say, "good boy, here's your reward for stopping your crying," and they start to spend their days having sex. Even after that, they continue to cuddle with their prey, consoling him with their body should he ever get sad again, and once it's healed, they resume giving him his endless reward. In other words, to them, a husband is not only an outlet for passion, but also an outlet for their overflowing protective urges, which means they have chosen that prey as their life partner; the one they will spend their entire life continually comforting.
Furthermore, their concept of "child" is far off from the human notion of what constitutes a "child."
Whether a male's age or appearance is actually that of a child is irrelevant, and clearly adult-looking men, even middle-aged men who outwardly look even older than themselves, will be contacted by them and treated as "children," so long as they have sadness in their hearts. In other words, to them, "children" is none other than a word that indicates human males in general. In actuality, since they appear before those who weren't given love and are unable to heal their sadness, mothers who shower their kids in love like the ones who tell those stories won't actually have their kids snatched away. Instead, it is those who can't get any love from their parents, such as orphans who never had anyone to love them in the first place, or adult men with nobody to even cling to that have a heart continuously filling with sadness that are the ones they would most likely visit.