The characters are probably 50% of why I enjoyed this series so much. I resonate so much with Haruhiko as a person, and his little freak outs are unreasonably hilarious to me! Ruru is just a sassy little chatterbox, but she brings so much energy into the room, and not to mention, she's irrisitably adorable! You might not appreciate Reina and Mai that much until a bit later in the series, but they grow on you as well. I will say, however that all of the characters, including Haruhiko (who is supposed to be highly intelligent), can be ditzy at times.
The character development didn't seem to be the creators' main focus of the show, they just sort of sprinkled it here and there, but they did it just enough for me to become emotionally involved. Especially towards the end, Haruhiko really starts "coming into his own", as they say, and I was glad they arranged that, but it seems like they just sort of threw it in.
I was also fascinated by the complexity of phantoms, and enjoyed seeing each different kind of phantom.
This series includes a few moments of ecchi, but it was by no means overdone in my opinion, and it was more comical than sexy.
There is also a subtle sense of harem elements in some episodes, but I enjoyed that it was all kept considerably low-key, and nobody ends up on a real date or even considering an official relationship. It really maintained the series’ light-heartedness.
Kyoani has yet again produced one of my favorites!
