Alright. This ova is a bit different than other ovas.
Story - 5
There isn't really any story in this, it's just some scenarios put in to show ecchi. But, this is exactly what the developers are going for, so it works out fine. The first involves Tamamo and Shirasaki in a drawing scene, the second shows Kana and Senri at the beach, and the 3rd has Kodachi and Sayumi (the blue haired hacker/restaurant worker) at the restaurant and then the bath. Each episode contains very revealing photos of the girls and has the girls talking to each other as well.
Art - 5
The art consists of photos
mainly. There isn't much animation at all, but since the anime was going for this, you can't really give them a low score.
Sound - 5
The sound isn't anything different from the main story.
Character - 6
The characters are all pretty much the same, just thrown into ecchi situations.
Enjoyment - 5
I didn't really enjoy it all that much, because I personally like full-animation and story. (most ovas are fine), but the small amount of story they added was enough to keep me watching. Other people might find the enjoyment to be less or more, depending on who they are though.
Overall - 5
These episodes are mainly focused on the people who love ecchi, and the people who will watch anything "Daitoshokan no Hitsujikai (A Good Librarian, Like a Good Shepherd)" related. But if you have time to kill, you misewell watch it.