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2d_animation animated animated_gif anthro backsack balls big_balls big_butt big_muscles big_penis bouncing_butt bouncing_pecs briefs bubble_butt butt butt_slap canid canine canis clothed clothing erection expansion flaccid flexing frame_by_frame genital_expansion genitals growth huge_balls huge_muscles huge_penis humanoid_genitalia humanoid_penis hyper hyper_balls hyper_genitalia hyper_muscles hyper_penis komboochie looking_at_viewer low_res male mammal monochrome muscle_growth muscular muscular_anthro muscular_male nipples paper_background penis penis_expansion short_playtime slap slapping_own_butt slapping_self smile speedo swimwear underwear underwear_only waffle_(ashwaffles)wearing_underwear wolf