Rule 34 Dev - 1boy 2018 2d 3_toes anthro anus arm_behind_head balls bowser feet grey_background half-erect hands_behind_head heels horn koopa lying male male_only mario_(series) monochrome naughty_face navel nintendo nipples nude on_back outie_navel penis scalie scalie_male scalie_only simple_background sketch slightly_chubby smile soles solo toe_claws toes uncut video_games zonkpunch|3197469264