What is the colored liquid that can be extremely thick or thin?

I believe your answer is Paint. Paint is a liquid used commonly on Canvas, but also used on a variety of other things depending on the thickness. If it's thicker, it can sometimes even paint on plaster, which is also common for paint. Paint can be an infinite variety of colors depending on Pigmentation, and oils used. If paint is thinner, it is usually used on Paper. Because it is thin, it will more than likely not bleed through the paper. I hope this helped!

Thanks!

~Steve