I thought she was using makeup to make herself look prettier

But it's the opposite. Typical ugliness = darker skin, freckles and frizzy hair but at least there's no glasses or braces I suppose. It's not really racist but a reflection of east asia's (and korea especially) beauty standards. Being asian myself it doesn't bother me as much maybe cause I'm used to the same thing in my society. Obviously not saying it's great but it is what it is in real life, unfortunately.
Still, I was drawn in thinking the FL is using the power of makeup to make herself and others prettier, but it's sadly the opposite.