 If you liked Higurashi no Naku Koro ni |  ...then you might like Mirai Nikki |
Both horror with a lot of mystery and questions. You may think you know something but then later you find you that you were totally off. Full of surprises.
report Recommended by MosaicSplash
both start out lightly but then become dark very quick. both have their forms of insanity in the character you least expect. Both series like to play with the minds of the audience until it chooses to clear everything up when it feels like. Highly recommend both.
report Recommended by AkuunKyande
Both anime are very dark and gritty, and neither one is afraid of killing off important characters. They also happen to share one particular plot twist later on. If you're looking for another dark and bloody series to watch late at night...alone...Higurashi is a great one to check out. Just be sure to watch the second season, Higurashi Kai, as well or a lot of questions will be left unanswered.
report Recommended by Greenwaves31