The elementals of Wyrlde are far less interesting than those able to cross to other places. There are many kinds of Elementals.
An elemental is always formed of the element it is. They do not have organs or skin or such, they are beings of unique will, the children and descendants of the Powers That Be. There are many different types of elementals, an entire ecology of them, like the great birds, the serpents, and others. One thing remains true: if an elemental exists in a shape in one, then there is a form of it in all others.
Humanoid appearing elementals are well known – Dao, Djinn, Efreet, Marid, etc. They may appear human-shaped, with great powers, and there is always one kind for each of the elements. As with all things, the elemental dimensions themselves are reflections of our own, and within them, these beings of great power are the people.
Earth and Fire elementals are always masculine, Air and Water elementals are always feminine. The rest of the dimensional denizens are generally without a fixed or given gender state.
Lastly, there are guardians of the world itself, separate from any God or other power, whose sole purpose is to protect the world. They are always people who are infused with this spirit and become lost in the memories of all the people they were before and separated from the regular concerns of mortal people – for people are their enemy far too often.