If you're looking for anime similar to Seraph of the End: The Vampire Shahal, you might like these titles.
The story begins in a village of vampires who are destroying their homes setting out into the world because humans are moving into their valley, but these "vampires" do not drink blood, nor are they immortal. Instead they all transform into animals, ranging from wolves and bats to snakes and crocodiles, the transformations being triggered by different stimuli for each vampire. For example, the main vampire, Toppei, turns into a wolf when he sees the moon or when he is scared. His little brother Chippei transforms whenever he sees anything round. Others transform at the smell of onions, the sight of a telephone pole, or a variety of other stimuli.
As a child, Inaho always loved listening to stories of her grandmother's immortality -- gained from a strange device known as the O-part. As a young adult, Inaho is finally ready to fulfill her dream: to find the O-part and gain immortality, just like her grandmother! But where can the O-part be found? Fortunately for Inaho, she has made a blood-pact with Mosquiton, a 1/4th vampire with a knack for servitude, and a nose for trouble. Joined by Mosquiton's ex-wife and two cohorts, the search for the O-part begins! That is, if the world isn't destroyed first...
After a breach between Earth and the netherworld opens up over New York, humans and creatures from other dimensions become trapped in an impenetrable bubble that surrounds the city. Forced to coexist in a new city known as Salem’s Lot, the shaky peace between humanity and the netherworld creatures is protected by an underground group of super humans known as Libra. When a case of mistaken identity brings not-so-ordinary delivery boy Leonardo Watch face-to-face with this group, he joins their ranks hoping to help prevent the destruction of the world by a group of monsters and madmen lead by a powerful being known as the King of Despair.