Do not watch this without reading the main-stories from the game first. Each episode compresses 2-3 hours of visual novel into 5 minutes. It's not trying to tell a coherent story that newcomers will understand, it's fanservice to see important beats of the original main stories animated. Given the task at hand, it's well done for the sheer amount of story it's trying to go through in that timeframe. Do give it a watch after you've read the main stories. I'm being forced by MAL to give a number score, but I'd prefer not to as shorts really can't be judged on the same scale aslonger media. If a similar level of quality and story was presented over a full season, its average score would easily be above 8, but we're stuck with what we have.