I don't think it serves it's purpose at lining and filling in at the same time because it's impossible to use without messing up the line of your lips, and the fill-in color doesn't cover your entire lip, so to fill in that gap is hard because you have the darker color on the upper part of the lipstick. I tried using a lip brush to just get the lighter color to fill in the gap but since this is more of a hydrating balm consistency, a brush isn't able to pick up much color. All that being said, just put it on your lips, and rub your lips together to mix both shades and you get a GORGEOUS flattering shade! It's not too opaque, and not too sheer! Just #beautiful shade "Pink Thrills"