What do you mean it's strange to see a bird eating meat? Eagle (smaller birds & land animals), condor (carcasses), seagull (omnivour but also eats human food), pelican (fish). This guy is pure... ah well, he's still just 20yo.
Anyway Rosewood does look like a noble's son. Ex-noble that is (& the girl who knows about the state affairs, she might be a princess). The way the adult treats him makes me think this world is also just as dirty as ours. Kidnapping, child trafficking, slavery & so on. & I think it's inevitable to assume that the people who abandoned the children are actually sacrificing them to the Griffin for the sake of the country's peace or something. The Griffin doesn't even eat human flesh.