I want to kill those "animals" from Volkihar, I dont like them at all, arrogant and useless an they stay all all the day eating humans and doing that stupid sound and since im the boss here, they deserve to die, I dont know how to attack them,if i try all vampires attack me...Id like to kill just them not the whole "team"....
PS: I dont know if they are essential or not, but you cant even talk to them, then their useless imo.

I don't think they are essential, and once a volkihar attacked me inside the keep, and I could hit him back without anyone doing anything. Try illusion spells to anger them?

They're essential, which is probably because they're little more than scenery. I mean, do you try to kill a tapestry?