Well this anime is good but there are some problem:
1: this is common for many people to figure out the serial killer in , 2nd episode.
2: they rune the relationship between the kayo and main character.
3: the manga writer created airi, I don't know why, she really don't do anything in the story to accelerate it, they created airi just like a toy so that the main character can happy with it, at the end.
4: they don't show us more revival.(that's my opinion)