Most of my characters are reasonably jaded on the subject. It takes someone particularly close or something particularly senseless/disgusting to get a visible reaction out of them among the death of bystanders or allies. It's really in how they approach the death of their enemies that they differentiate.
The cast of In The Service
tend to be, or quickly get, jaded on this subject. There's really damn jaded
with Wolkenritter, who regard the deaths of their enemies as about as significant as the deaths of the hundreds of thousands of germs they kill washing their hands, to only a little jaded, with Tre's inability to remember the faces of anyone's she's killed despite being a cyborg with perfect recall and occasional struggles with whether the necessary act was also moral. (I'm deliberately leaving out the sidestories, but no, Vivio wouldn't take it well at all.)
The cast of Night Life
varies too; one of the Knight Sabers (excepting Sylia) would probably have a temporary breakdown if they discovered they'd killed an actual human being unless they were seriously provoked, while K-11-2 is almost undoubtedly more sanguine about the prospect due to being much more familiar with death in general.
edited 16th Dec '11 8:23:46 AM by Night
The last thing many a boy from Side 3 will ever see; a Federation beam weapon in action.