Gintama
The Reaper by Day and the Reaper by Night (7x14)
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Recently, there has been a bizarre string of murders around town. The victims have all been killed the same way, with their heads virtually severed, bar a small strand of flesh. Gintoki, whilst stumbling home drunk, encounters what appears to be a reaper who asks him to help with their ritual suicide. He will soon discover just how the two are related.