 If you liked
Owari no Seraph
|
 ...then you might like
Devilman: Crybaby
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They both have a slightly BL relationship between the two main characters with similar dynamics in terms of moral tension. The characters were friends from when they were young and parent-less.
There are some shared themes of existentialism, Biblical references (angels, demons, apocalypse), war between different species (humans and demons/vampires), & characters with dubious intentions.Seraph of the End is a more light-hearted and typical Shounen, while Devilman is very dark and psychologically disturbing.