This is a lovely movie about three students trying to find their way in art, love/sex, and life in general, and I reckon it shows about equal parts of these three areas. You wouldn't be able to tell from the cover of the DVD, which focuses on one of these and obviously tries to sell the film as porn, which it clearly isn't. This is underlined by the very unsubtle English title. I guess the original title, Castillos de cartón, is to be understood along the lines of "castles in the air" or "house of cards"?. The script is based on a novel by Almudena Grandes with the same title: Castillos de Carton (Coleccion Maxi)
The three characters are set apart from mainstream society not just by their creative urges but also by their unusual 2+1 love life, which they don't dare to spell out to their parents. This isolation increases the pressure on each of them to find fulfilment within that triangle. To me, this was the most important aspect, and it was acted very convincingly. The art could have been used even more - I love the triangular arrangement where they draw portraits of each other, but their art isn't really used to show how they see each other.
I'm subtracting one star for the horrid title and cover of the DVD, and also because on my laptop it insists on leaving a wide black margin on all sides, using less than half of the available screen area. Oh, and there are no bonus materials apart from the original trailer.