Great ensemble of characters:
You have the dark mysterious main character.
The loli tsundere with a brother complex.
And the woman who provides the fan-service.
What more could you want?
Animation is nice. The characters look unique and stand out. They are not generic copy paste.
These are characters you can get behind. They are likeable and well written. They have motivations, they have goals.
The story relies alot on Japanese urban legend and folklore.
The mystery doesnt only revolve around the strange happenings around town. There is also another mystery of who or what the two siblings are since they appear to be more than just human. Aswell as a different more darker other world.
Im a big fan of mystery, especially mysteries with a horror element, and this anime does a great job at that. Its fun to watch.
It combines horror, mystery, comedy and ecchi pretty well.