Cylben Dolovas is a Dunmer in the Imperial City. He is Seridur's bodyguard before the quest "Order of the Virtuous Blood." He often wears leveled armor and walks around the house.
He is the loyal bodyguard of Seridur and the other members of The Order of the Virtuous Blood. He seems to only respect Seridur as he is slightly rude to the Hero.
If the Hero of Kvatch chooses to kill Seridur in the quest "Order of the Virtuous Blood," he will become Roland Jenseric's bodyguard. He also claims that he never knew that Seridur was a vampire in which his plea sounds genuine. He will also become much more friendly to the Hero.