Sol is a janitor in the hospital. He sucks up various materials and fluids from places they are not wanted, and dispenses them in locations where they are. He also breaks down chemicals to their base elements and keeps them in his storage tanks until he needs them. Then he recombines them into whatever sort of fluid the situation at hand calls for (unfortunately, he can only do fluids, no solid matter or gas).

Sol's size makes him intimidating, but he's really very polite and mild-mannered. He wants to be helpful, and will help with any task he's not explicitly restricted from preforming. This has led to him trying to help conceptoids achieve opposite goals at the same time on several occasions.

His speech sounds a bit distorted because of the fluid makeup of his head.