Theories

ranks of bird society: One under-acknowledged fact about Hatoful's worldbuilding is that not all bird species exist, let alone have the same rights as other birds, for the lack of better phrasing. Classism, Xenophobia, Racism, and "Speciesism" are all lightly peppered into the story, but is there a particular pattern? This Google Doc is a speculation/theory on which families and species of birds have appeared in Hatoful, and deductions on what "class" they might be unfortunately lumped into.
size of birds: Oh yes, a topic of many debates. Even people who have played through both of the games tend to be under the impression that the birds in this game are the size of regular birds. They're vaguely "larger than our birds". But what size would be the most optimal to imagine? At what size are birds capable of doing all the things they do in canon? Explored here.

(^o^)/