anthro
avian
big_butt
bird
butt
digital_media_(artwork)
duo
echidna
escopeto
extreme_gear
female
from_behind_position
hi_res
hirundinid
huge_butt
knuckles_the_echidna
male
male/female
mammal
monotreme
muscular
oscine
passerine
sega
sex
sonic_riders
sonic_the_hedgehog_(series)
superbunnygt
swallow_(bird)
wave_the_swallow
