In general, it's an edgy anime. It has a high school setting and plot, the only difference being that it has psychotic and edgy teenagers. I've not seen School Days (and I swear I never will, no matter what), but I've seen the ending of School Days, and I can say that if you take the edginess of the ending of School Days, and made it into two 40 min episodes, you'll get Electromagnetic Girlfriend. The only reason I personally gave it an 8 is because the first episode was legitimately good. The second episode was trash and edgy. Why have I mentioned the word "edgy" multiple times? To emphasize how edgy it actually is. I don't want to invalidate others' opinions, but whoever said that it has a dark atmosphere to it, they're totally wrong and I've seen better anime with a more eerie atmosphere. I'd say that this anime is more like a guilty pleasure than an actual good show.
Also that's 1.5 hrs I'm not getting back lol.