That space under your knee; the scientific name is not known. Generally this area does not grow coarse hair unless you accidentially rub rogaine on it. If such a thing was done, you'd have a hairy knee-pit.
Girl 1-"Ohmygod, I was shaving my legs last night and cut my knee-pit! Now everytime I squat down more blood gushes out D:"
Girl 2-"Yoh at least your older brother didnt wipe rogaine all over it when you were sleeping, my brother did and now I have a hairy knee pit!"
When a male and female are aroused the male takes his enlarged penis and sticks it behind a woman's knee and beats to his own rhythm
Jack and Emily are naked in bed so emily sands up and jack whoops out his fat cock and sticks it behind her knee and moves his torso back and forth and thts knee pit sex