What frustrates me is that apparently, I missed some Hetalia episodes without knowing (aside from the Hetaween episode).

I uses gogoanime up until Beautiful World, so it's reasonable that I'd somehow miss some Hetalia episodes. Apparently, though, there's a Beautiful World/World Twinkle episode I didn't watch?? It must have been Beautiful World because I actually throughly looked through the World Twinkle episode list??

This irony, though.