this anime is AWESOME, i liked it very much. the plot is simple and easy to understand, and funny as hell. the art is 2011's work, so i don't need to comment on that, but i really commend they're use of echi to the point where they're not showing anything, but you know whats going on. the voice actors are fine, although i didn't focus on that area, but voices were funny. the characters themselves were so hilarious, how Jirou falls into one mess and then falls to the next. overall, i enjoyed this anime very much and i hope for a next season.
p.s. i think the people who made this anime switched the episodes 12 and 13.