rule 34 animal genitalia animal penis anthro balls outline biceps big penis bikini black penis blue background brown hair bulge clothed clothing crossdressing equid equine equine penis erection erection under clothing freckles artist fur genital outline genitals glistening glistening body glistening fur grey body grey fur hair hair over eye hand behind head hi res looking at viewer low angle view male male only mammal medial ring monotone body monotone fur muscular muscular male one eye obstructed penis penis outline pose presenting presenting penis raised arm simple background smile solo standing swimwear tenting wet 3810730