Not necessarily.
Van doesn't consciously focuses his Charm on others.
It is basically a passive skill, whose affect can be negated by anyone with strong will, like Borkus (he had said before that he can negate Van's charm affecting him if he wanted, but doesn't bother to do so anymore after their initial meeting as he trusts him now).
As for the Charm skill, it just creates a favorable feeling to beings who are related in someway to the Death attribute (either physically, magically or emotionally
And for Van's Charm to have affect others, not only they need to clear the requirement of being connected to Death attribute in some way. They must also have either neutral or no harmful feelings towards him.
If anyone has any feeling of wanting to hurt Van or anyone close to him, they wouldn't be affected by Van's Charm (seen by how many of the other Vampires who faced Van didn't show any favorable feeling towards him, as they had come to kill him, while Eleonora also came with the same reasoning, she herself changed her opinion midway which allowed her to be influenced by Van's Charm).
The only exception to this rule are the Spirits & Ghosts who are 100% attracted to him no question asked.