Zettai Heiwa Daisakusen begins with a rather heard-of story of 2 people from feuding countries coming together with fake love to end the war which slowly turns into true love.

(Skip to the bottom at "Overall:" for a basic summary...)

Story:
Even with the somewhat used base story, the plot is entertaining in how it is able to maintain a good balance of romance, comedy as well as dramatic events.
Personally, there is also a good dose of added realism from the political aspects of the story that I thought would probably be ignored in light of the romantic comedy.

The comedy of this manga is mainly the lovers' quarrels between the two main characters and the minor characters' presence and behaviour which all bring a very sweet and cute aspect to the plot.

However parts that the manga could improve on would be the clarity of some aspects of the plot such as the ending. (Find out for yourself)
Even so, I am rather amazed at how the mangaka manages to turn the almost impossible situation into a happier ending (which shouldn't be too much of a surprise) with more emphasis on a light and comedic atmosphere again.

Art:
To me, the art is rather appealing and interesting especially the simplified smaller panel pictures that bring out the comedic effect of the situation and characters' actions a lot more.

The clothing of the characters have nice detail to them that give them a sense of realism. What I liked was how the mangaka manages to maintain a level of character distinctions even when using more or less the same eye-style on the characters, because this is usually an aspect that is left out.

Characters:
The characters do not necessarily have a lot of realism to them that make up a psychological story, but they do have some extent of depth and history behind them that make them likeable and interesting.

Overall:
A very cute and sweet rom-com yet exciting and on-plot enough to have a mix of politics, drama, (a bit of) realism and action included.
If you're looking for a bit different type of shoujo rom-com manga without too much of the stereotypical nonsense, this should be on your list. :)