Of all the rules of Dark Reflection: Spectres, the ones concerning Rapacity and Emoting are the most confusing and the least convincing.
Being is the equivalent of Willpower for a Spectre and it's linked to his higher Dark Passion's emotion.
[..] Whenever a spectre encounters a mortal or wraith with a Passion of the same essence of its Being, the spectre must make a Being roll (rolling as many dice as it has permanent Being) or become Rapacious. A Rapacious spectre attacks the target by Emoting.
Emoting is an attack launched by a Rapacious spectre against the permanent Willpower of a wraith or a mortal, triggered by the spectre's Being. A successful Emote drains the target of permanent Willpower, and increases the Spectre's Being by an equal amount. To Emote, the spectre must overcome the target's Willpower with its Being in a resisted roll. Each success rolled by the spectre that is not canceled out by the target's successes equals the number of point of Willpower that the spectre drains. Mortals, who often have only a few points of Willpower, can often be killed by an Emoting spectre. Their bodies when found, appear to have died of fright or some similarly intense emotion.
Dark Reflection: Spectres page 54
My first problem is how that looks like? Let's say you are a Wraith and find a Doppleganger who you thinks is your friend. As you have the passion "Kill my murderer (vengeance)" and the spectre's being's essence is also "vengeance", the Spectre rolls for resisting Rapacity and fails. So the Doppleganger cannot contains himself and emotes you.
First, what do you exactly see? How does he make the attack? Physically, mentally, or how? Do you notice it?
Second, isn't stealing permanent Willpower too heavy? I think Spectres would be the only World of Darkness beings capable of doing that, and they would have it built-in, at no cost (neither in character creation nor activation) and many times they wouldn't even be able to avoid it.
Lastly, do Dark Passions trigger Rapacity rolls, or only regular Passions of the Wraith?