When an "earth elemental", born from concentrated earth elements, is joined with "mamono mana", it usually becomes a monster called a "Gnome", but if the mana is too powerful and it melts the earth elements, it will fail to become a gnome, instead becoming a "dorome", a being whose nature is closer to that of a monster than an elemental. After being melted by mana, their earthen body becomes a body of sloppy, loose mud, and their sensually melted heart also becomes devoted to monstrous desire and pleasure. When they spot a man, they'll attack and attempt intercouse while making an ecstatic smile.
Their intelligence is not very high and their movements are sluggish too, so if you notice them, escape won't be difficult. However, given that they are comprised of earth elements, they can merge with the earth and move freely below ground, only to suddenly appear at a man's feet and instantly seize him by wrapping him with their muddy body. While they do aggressively attack humans, their disposition is extremely gentle, and when they restrain a man, it's like a tender embrace. Their mud is warm and soft, and a man will be enveloped in a comfortable pleasure even if he just surrenders himself and soaks in it.
The sex isn't very intense either. They'll cover the man's body entirely with their loose body as if to firmly embrace him and gently shake their hips, providing the man a melting pleasure. When monsters copulate with men in this manner, they naturally make an ecstatic expression the moment they sip mana, but it seems that doromes are able to get in a pleasant, happy mood even by just taking a man inside their mud and enveloping him. It is said that those that have obtained a husband make an extremely ecstatic expression as if they were right in the middle of sex even when simply embracing their husband in their muddy arms.
Since they themselves are earth, even if their body crumbles or gets smashed, they can just create a new body from the ground, and therefore physical attacks won't have much effect. Additionally, they can take in the surrounding mud and earth, make it part of their own body, and freely control it, and they can even make multiple copies of "their own body" from the earth. Sometimes, regardless of the fact that there was only one of them, before you know it, you'll find yourself surrounded by them.
How much earth they can take in differs depending on the magnitude of the mana possessed by the individual. Normally, the limit is only several bodies' worth, but they say that sometimes they swell so much that all the visible ground, or every place all over the walls, floor, and ceiling of a cave, will become part of the dorome. If a man carelessly sets foot inside one of them, he will end up having his body covered in countless muddy female bodies that suddenly appear around him.
It's Christmas, but the new race this time “Dorome”-san has nothing whatsoever to do with it! The encyclopedia world has a bit of a time difference with the real world, so the monster scholar couldn't keep up with it... (an excuse). When a gnome, which is a monsterized earth elemental, is being born, if the earth elements melt due to mamono mana, and it fails to become a gnome, then the resulting monster will be a “dorome”. Supposedly, being enveloped in their body is warm, pleasant, and restorative, almost like a mud bath at a hot spring...
- TL Note: Trivia from tweets where Kenkou answered questions about dorome from various fans. The questions are summarized by Perentie, the answers translated by Brolen.