Vanish from Mind's Eye
Your power has advanced to sugh a degree that you may actually disappear from plain view. Even if you are standing face to face with a mortal, you may exercise this power and simply vanish. Those who witness such a disappearing act, especially mortals, are normally stunned with indecision for a turn. One member of a large group might be able to react (such as to fire into the space where the character vanished), but this is the exception. Moreover, mortals with low strength of will may actually forget that they ever say you at all.
The player must roll Charisma+Stealth (difficulty is the Wits+Alertness of the target). If more than three successes are obtained, the vampire completely disappears from sight. If the player obtains more successes than the target's Willpower, she completely forgets the vampire's existence, but the vampire must leave her presence immediately or be remembered.