Encyclopedia Entry
A type of mermaid living in the Zipangu region. They have the body of a long slender fish covered in a mucus membrane. The slimy mucus secreted from their body contains many compounds that restore vitality and stamina, and since they themselves have it inside their own body, their body is also full of an unmanageable amount of stamina and lust.
Normally, their lascivious true nature is masked by a soft and gentle demeanor, and a devoted appearance befitting of a race of Zipangu, but their unconcealable charm oozes out from bits of their speech, the way their body wriggles whenever they move, and their posture. They don't directly seduce men, but nevertheless, because of their appearance, they're good at getting men in the mood, and in most cases, men will be eager to seize their heart.

Their body is covered in a mucus membrane to protect them from desiccation. When wrapped in this slippery body, even if one tries to grab their body and pull them off, one can't get a good grip. They can adjust the state of the sliminess of the mucus membrane at will, and without the slime, it makes it easier to grab them. On the other hand, they can also make those who touch them slip to the degree that they want. The hands of men that try to touch them slip in the slime, with the extra momentum causing them to touch their breasts or genital area. When a man panics and twists his body in an attempt to get away, he'll slip even more, pressing against and knocking down their soft body.
By the time he becomes aware of it, not only will her body be coiled around him, the man's four limbs will also be wrapped around the girl. Even if it should just be a casual touch, one will end up entangled and locked in a grapple with them.
In this way, they don't just seize a man's heart, they seize his body using their mucus and create a situation where he can and will make a move on them. Before they know it, men who strike their fancy will find their body and heart seized in this manner and gradually end up having sex with them.
Their soft body has just the right resilience, and being covered in it feels pleasant. It's as if a man's penis will melt when having sex wrapped in their body. During sex, a man is made to drink mucus transferred mouth-to-mouth, and mucus coils around his penis with wet sticky noises, continuously restoring his vitality and stamina. No matter how much they have sex, they never get exhausted, and the more they have sex, the more his stamina increases. A man will come to desire to keep having longer and more intense sex with them.
Those who have a husband expose their lascivious true nature and desire to service their husband with their own body. Due to their devoted nature, they make good wives who pour their heart into taking care of their husband, but the home cooked meals they make every day always have their mucus mixed in. It's highly nutritious with a rich flavor which will appeal to their husband's tastes, and continuing to eat the food every day will build up his stamina to the point that he will always have an excessive amount of vitality and stamina, and when their husband wants sex at every opportunity, they will gleefully accept it.
Since he can get energy from having sex with them, even if the husband does have a job, he'll develop a habit of having sex with them until they're stained cloudy white after eating breakfast, before heading off to work.