Ghoul

Name: Ghoul
Normal Life Expectancy: Immortal
Background: Something that Vampires and Ghouls have disagreed on for a very long time is on which species came first. Most Ghouls believe that they came to be because of God's punishment to Cane for killing his brother. As such, because it was murder that he caused, it was by murder that he would have to survive - off of the flesh of his victims.
Either way, just like Vampires, they're an old species, which have been keeping as quiet about their existence as possible for thousands upon thousands of years.

Disadvantages: Much like with any creature if you cut off their head they're done for, it's as simple as that. They also must feed on the flesh of humans to survive and maintain their strength.
Special Customs: It is said that a Ghoul is created by one Ghoul removing their heart and putting it into a chest of a freshly dead human being, a Vampire then uses their blood (which contains healing properties) to cause the heart to heal again into the Human's chest, thus bringing them back to 'life'. Though, some debate this, and say that there are other ways.