Vampire

Vampires are a species of supernatural beings in High School DxD.

Appearance
While physically similar to humans, vampires have a set of sharp fangs in their mouths.

Abilities
While the full extent of their abilities have never been entirely explained, some vampires are known to be able to control bats, and transform into a flock of them and use them for reconnaissance.

They can also gain more power by drinking the blood of certain beings, such as when Gasper drinks Issei's blood.

Weaknesses
It is known that most vampires are vulnerable to sunlight and garlic. To what extent this hurts them, however, is unknown. Vampires also need to drink blood occasion to stay alive.

Daywalker
Daywalkers are a special variant of vampires who are immune to the effects of sunlight, although they do still seem to feel some discomfort.

Dhamphir
The Dhamphir are hybrids of vampires and other species. Any effects this may have on their abilites have yet to be fully explained.

Known Vampires
The only known vampire in the series is Gasper Vladi who happens to be both a daywalker and a dhamphir.