I mean, there's not much to say about it.. and I don't even know why I'm writing a review. It's a single special episode of 20 mins, so during the time you read reviews about it you might as well just watch it.
What's it about? Take Zero no Tsukaima, and move it to the beach. Girls in bikinis, boys who want to peak, a bit of Louise x Saito. That's it.
And since I have to write a longer review.. the story is absolutely amazing! I would've never thought to see such a complex, flawless story being put in a mere 20 minutes. I was completely blown away!