Now the ova for the actual anime with 12 episode is quite confusing. Yes the scenes are full with sekkusu, ecchi and yuri but the six 2 minute long episodes are scattered. They are all before the final ending of the actual anime. So if you have watched the full anime first then went onto the specials; like i did, you'll be a bit confused. you'll know what ultimately happens at the end but i guess you get a sneak peak behind the scenes kind of look of what was going on during the whole ordeal.
Worth the watch if you enjoy yuri and also very short.
Check out my yuri list if you would like to see more animes based on the yuri tag.
And please ask if you want a review on any anime within my lists before you decide to actually check out the anime, and i'll be more than happy to help.