 If you liked
Hellsing Ultimate
|
 ...then you might like
Vatican Kiseki Chousakan
|
... because Christian imagery and Nazis are exotic or something.
Hellsing is heavier on the Nazis and VKC is more focused on Catholic esoterica but plenty of both in each.
Both are gratuitously dark, with plenty of death but also plenty of black humour to lighten things up. Hellsing being the gorier of the two.