Thick squads, thin pony knees?

[ctchristopher]

Hey it seems my upper quads are looking big and thick and when im sitting down in the car or on the bus, my knees look super pointy. With my friend sitting next to me my upper quads are thicker than his but moving closer to the knees, his are thicker. My knees just look like there poking out, there doesn't seem to be much muscle in that area. I know knees are a bone and not a muscle but they shouldnt be pointy like that if there is muscle mass surrounding them. How can i build up more muscle there? It's the tear drop area im lacking in, right above the knee making my legs look skinny above the knee.
Am i just lacking overall mass? I see fat ppl sitting down and there knees area look very thick.