Guilty Crown: 4-koma Gekijou is a chibi version of Guilty Crown. Each episode is a bit over 1 minute, the animation barely has movement and it doesn't contain any plot progression at all but it's still enjoyable. Because of all references to other anime, for example in episode 3 Shu makes fun of Kirito by saying he couldn't just defeat everyone because he is not in SAO. It also contains more vulgar language than it's prequel, Guilty crown. Words like shit, fuck and fap are thrown around as if they were normal.
Conclusion
If you watch Guilty Crown: 4-koma Gekijou to see more plot progression you would be terribly disappointed. But if you don't care about plot, and just want to see characters banter with each other or make fun of other anime then you would find Guilty Crown: 4-koma Gekijou quite a delightful ride.
