This is an act where the male (or the dominant sexual partner) proves his dominance. To accomplish this the inferior partner must collect the semen in his hand during sex, you do this by pulling out at the last moment. You then cup your hands like an umbrella over the glans before ejaculation and collect it all. Then the dominant partner stretches his scrotum out, making it kite like in shape, and the inferior partner spreads the semen out on the scrotum.
Then the dominant party drags his scrotum over his partners face, and thus the rite is complete, and he has proven his dominace.
"Your sister didn't want to acknowledge me as the dominant one in our relationship, so I gave her The Butter Kite. Guess who's in charge now!"