2) The Senshi attack first.
Wrong, wrong, WRONG!  The Senshi attack a Yoma when its draining
energy from humans.  So, even if the Yoma are living things, it comes
down to a matter of destroying one life form, instead of letting it
live and kill others by its very presence alone.

I don't really watch the show, but does the energy draining
really kill the people, or weaken them a lot, or what?

It depens on how much energy is drained.  If enough energy was drained, 
they WOULD be killed.  I don't think that actually happens, but during
Sailor Moon S, anyone whose heart crystal is removed is as good as dead
until the heart crystal is replaced - and the villains have no intention
of replacing them.
___________________________________________________________________________
Andrew Dynon, Eternal champion of all things Iczer and Mekton-Z

"This sudden explosion of flashy special effects can mean only one thing - 
 It's... PARTY TIME!" - Samurai Pizza Cats, "Those Transformin' Felines"

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