"Koisuru Asteroid" is one of those anime than unless you're interested on its subject matter you won't be liking it as much as you'd want to. What if I told you that's not always the case. What if I told you that the characters could make the story rather the aforementioned "subject matter"? "Koisuru Asteroid" is certainly one of those anime, and I'll prove it to you.
Yes, because the characters are so likable it makes me ignore the fact i've never been interested in astronomy. It's fascinating because throughout the anime I learned so much about something that it never mattered to me and all this thanks to its characters interaction, which I have to say, it's actually hilarious. They somehow make it possible to be hilarious and at the same time, explain further the astronomy. I actually did some research and whoever wrote the script did a good job of explaining things in the best way possible. It's not confusing to say the least and the comedy makes it better. I'll be honest, if it was a serious show i would have probably dropped it long time ago, and while I like it when something is serious, some things have to be hilarious, otherwise it wouldn't work as it should.
The story is also nice even though sometimes it feels like most of it is filler and does not progress the story. This has mainly to do with the amount of characters and the fact it's set at school. Considering the amount of characters, lets very little to development but I don't think it wouldn't matter that much since the story is plot-triven rather than character-driven. The main point of the anime was explained extremely well and that's what matters in the most. Everything else irrelevant.
"Koisuru Asteroid" is clearly not for everyone... in fact I dare to say it's just for a group of people but if you ever wondering if it's worth watching then my answer would be... thoroughly. Watch it at least for the characters as they're so damn lovely.