re: Tumblr osmosis, it's pretty much insane amounts of homo subtext between everyone, which is... just like Madoka in that aspect, really. As someone who's not terribly invested in the yaoiz part of it, I was still very much able to enjoy it. Cute show, you're pretty much guaranteed to be horribly endeared to at least one character.

It's 9 out of 12 episodes right now, and there's also a prequel light novel called High Speed. So it's pretty short as far as canon goes.

Here is a clip that's pretty indicative of the majority of the show, although there are darker and more serious plotlines occasionally.