You want to see an five minutes anime who gonna surprise you to the begin to the end? If you'd like, this is Null Peta. A non sense anime who show us a simple plot, but with a lot of plot twist. The storytelling, keeping in mind the script. is organic for your genre and becoming a positive surprise. The plot can be a little confusing throughout the episodes, especially in the middle of the anime, but this only highlights the no sense genre in the anime. At times you might even think "ah this happened because the anime has low budget", may even be that, but thedevelopment of history makes everything believable and natural.
About the characters, you want more development than this? It's totally organic, you understand who the characters are and they're there for a reason.
Peta's maturing is certainly one of the best and best structured I've ever seen in anime.