Prussia/Austria

Prussia/Austria is a popular slash pairing in Hetalia: Axis Powers, involving the characters of Austria and Prussia.

The pairing is sometimes referred to as the Water and Oil Pair, based on how water and oil don't mix, much like how these two characters cannot get along.

Wars
During the War of the Austrian Succession (in which Austria says the infamous vital regions line), Prussia was determind to claim Silesia for himself.

Another war between them included the Seven Weeks War, which ended in Prussia's victory.

Modern Life
Prussia takes pleasure in annoying and humiliating Austria in whatever ways he can, mostly bothering him when playing the piano or appearing uninvited (as seen in Episode 24, when he pops out of a bush to make fun of Austria on how cheap he is). Prussia always comments on how Austria is 'too uptight' or 'needs to loosen up', while Austria thinks Prussia is childish and irresponsible.

Prussia once proclamed on his blog that Austria and him were staying at Germany's house. Austria also gets annoyed because Prussia dumps a lot of unwanted items/items he was conned into buying onto him (for example, a panda that was supposed to bring 'happiness' sold to Prussia by Hong Kong).

In the Christmas webcomic Prussia and France are seen trying to strip Austria, with Prussia demanding that having Austria strip and be humiliated will be his Christmas present.

Fan Speculations
Some fans believe that Prussia's taunting and teasing is a way of hiding his true feelings about Austria, as he is seen crying whenever he sees Austria and Hungary together. It is more likely that Prussia holds affection for Austria rather than Hungary, as he only stalks Austria.

Others think since Austria talks about hating Prussia so much or just talks about him in general, he secretly holds much affection for him, despite his stubborn attitude.

Webcomic: Extra Stories

 * Maria Theresa and the War of the Austrian Succession
 * Maria Theresa and the Seven Weeks War
 * Summary of the Austrian Succession
 * Christmas 2007 Summary (Part 6)
 * Liechtenstein's Journal of Swiss Dopiness