What is Underbutt?
1.
The distinct area off the bottom that is at the lower part of the gluteus maximus. Usually the underbutt is highly regarded in terms of attractiveness. Often the underbutt is discovered at the beach when womens bikinis do not cover the whole area of the bottom.
Amy has an excellent underbutt
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2.
The second butt created below the original butt by tight underpants, where the elastic is doing all the work, under tight pants.
in my jogging tights i have an underbutt and a
muffintop and in between is myba-donka-donk
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