Rule 34 Dev - age_difference ambiguous ambiguous_penetration brother_and_sister cub cutie_mark female feral feral_on_feral filly furry horse_penis incest large_penis larger_male legs male my_little_pony my_little_pony_friendship_is_magic penetration penis ponpu pony purple_eyes purple_fur pussy sex sheath shining_armor siblings size_difference smaller_female spread_legs testicles text twilight_sparkle white_fur younger_female|3544797231