They start out like this

So parasites are made by the Reaper aka. Mr. Grim or whoever you wanna call him he had man names. And when born come out as those lil thing above. When born grim will help them find a human body so they'll be humanish. These parasite come in ball kinds of colors but are mostly black and or any shade of grey or black. Like this:

this is Jackie one of his sons

here's Jackie and another sibling,

here's that other sibling lexton.

This is all I have of them lol but yeah.