Japan Is a Paradise! Tears in Wakasa! Blue Seed : Season 1 Episode 16

Kunikida heads out to investigate the death of his old friend, and is greeted by his young wife who holds a deadly secret. Meanwhile, deformed bodies begin piling up as sightings of the ""Thousand Year Nun"" (a strange woman who would stay young forever by devouring the flesh of a mermaid) are reported.