The nature of predators is by far one of the most popular HFY stories, spanning several entries. One of the highlight alien species are the Krakotl, a race of bird-like aliens that have a semi-antagonistic relationship with humanity. Would highly recommend. Trained on as many images I could find, should do males and females well.
Trigger phase: Krakotl_nop, alien, avian, beak, bird, feathers
Might want to add blue feathers if they come out the wrong color.
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