Rule 34 Dev - 1boy akihiro_altland ass back_muscles back_view balls_in_underwear bara black_hair bulge cum cum_on_ass fundoshi fundoshi_only grey_background gundam human human_only looking_at_viewer looking_back male male_only muscle muscles muscular muscular_male presenting presenting_ass presenting_butt solo_focus spiked_hair spiky_hair sweat sweaty underwear underwear_only usada! white_underwear yaoi|3830606480