Rule 34 Dev - 2013 alpha_channel anthro biped black_blindfold black_hair black_hooves black_penis blindfold bondage brown_collar collar ebonyrubberwolf equid equine genitals hair hands_behind_back hi_res hooves horse male male_only mammal penis sensory_deprivation simple_background submissive submissive_anthro submissive_male transparent_background|7635608048