How does the Soul Eater's Energy Drain touch work?

Question

I've been doing some theory-crafting and attempting to build a high-level villain as a gestalt character, and I'm not sure the combo I was planning on using actually works.

In the Book of Vile Darkness, the Soul Eater prestige class grants the Energy Drain ability (emphasis mine):

Energy Drain (Su): A soul eater gains the ability to drain energy, bestowing negative levels upon its victims. Beginning at first level, the touch of a soul eater bestows one negative level on its target. At 7th level, the soul eater bestows two negative levels with a touch.

Is this a touch attack, that has to be made as a standard action? Or is any flesh-to-flesh physical contact enough to trigger the ability? Or is it somewhere in between, requiring an attack versus touch AC, but not requiring "charging up" the way something listed as an actual "touch attack" does?

How does it interact with other abilities? Could a monk soul eater attempt to touch a target as part of a flurry of blows, since it's not a weapon (and is thus, arguably, an "unarmed" attack)? If so, could they make energy drain attacks for all of their flurry of blows attacks, since there is no recharge or limitation on uses?

If a soul eater has natural weapons (and they probably do, since the PrC requires you to be a living non-humanoid), does hitting a target with a natural weapon trigger energy drain? Obviously the attack would have to be against regular AC instead of touch AC if natural weapons are being used, but could a natural weapon attack inflict the energy drain effect in addition to its damage and other effects?

Loosely related: Can I use a full attack and natural attacks in the same round?

Answer 1

Oh! Well, that turns it from some complex mass of edge cases into a simple proposition.

1. If you go by the completely psychotic RAW or the Wizards FAQed answer on natural+flurry, then the flurry would not drain but any additional natural attacks would. Of course you'd have to get additional natural attacks, which just being a human soul eater or whatnot wouldn't get you.

2. If you go by the more reasonable interpretation accepted as the answer on the other question, and that's how I'd rule, then I'd also rule that sure, it's a flurry but "with" natural weapons and so totally, the energy drain would proc on each. It says "touch" after all, and considering an unarmed attack not a "touch" stretches in-game-world credibility.