 If you liked D.Gray-man |  ...then you might like Hellsing |
They both fight evil demons, both sometimes have a lot of blood, and D. Gray-man reminds me of Hellsing. Also, both have a vampire who is a hero. (D. Gray-man a little later on)
Heavy religiously based, both about organizations held by the church (in Hellsing there are two, one of the English church and another on the Vatican while in D.Gray only appears the Vatican) that fights demons/vampires. The atmosphere is dark and gothic.
report Recommended by BlindNoldor