The premise is basically about a unsocial kid that has the deus ex machina as an imaginary friend. His "friend" gives him a diary that recounts all his future actions day by day, and it all appears getting better for him when he notices that he's being part in a crazy game to kill or being killed but other diary holders.
I'd started following this series in its manga form, but definitely I think where is at its best is anime form. The story is a fast-paced psychological thriller in which crazy twists happen. If you have watch Higurashi because of its contrast between creepy/cute elements this series is for you.
P.S. The opening its definitely one of the best I've seen.
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