[DISCUSSION] Biggest fears/worst memories

[boscaresque.livejournal.com]

So I was reading Harry Potter and the Prisoner of Azkaban earlier (yes, I know :P) and during the parts involving boggarts and dementors, I started thinking about Hetalia and what each nation would see if they encountered either of those creatures. What would their boggarts turn into and what would the dementors force them to relive? I feel so nerdy for even thinking of this

Basically the question is: What are each nation's biggest fears? What about their worst memories? And alternatively, what are their best memories?