2 adjectives to describe backside

Asked H. Conner, Esq., the signification 'of "Monguagon," He replied, the true name is Mo-gwau-go [nong], and was a man's name, signifying dirty backsides.

"Whack!" There came an indignant grunt, followed by a flabby groan and a straining and squeaking of the jerry-built staircase as Kasheed Hassoun vigorously applied a lath to the horny backsides of Eset el Gazzar.

2 adjectives to describe  backside