@plastic_sludge
Let me introduce you to the concept of "anti-hero." A guy who goes in with no backing of the law to kill the bad guys is never going to fit the standard definition of a "hero." If the cops busted in right after this whole bloodbath, the assassin dude isn't going to get a pat in the back, a blowjob in the parking lot, and a medal from the mayor afterward. He's going to get arrested, and get arrested for premeditated ("I will kill") first degree murder, ie. he's a "bad guy."
In the game talk you seem to be most familiar with, this was "fucking kill everyone" mission, not an escort mission or save the hostage mission. In the escort or save the hostage mission, if you kill the civvie, the mission fails and you gotta redo. But in the kill everyone mission, if a civvie dies, you get some points docked and don't get the 100% clear, but if you choose to continue on, you can.
So you're an anti-hero assassin, living in the shadows, doing things the regular cops cannot do, and you think you're going to have a 5 minute interview and a background check with everyone you see in the organ trader's hideout? Why? That's what a cop would do. Hell, that's what a cop would HAVE to do. They would have to get a warrant, set a perimeter, send in a negotiator, and have a nice slow and boring 72 hour siege until Papa hires a really high-powered lawyer who somehow gets the little brat off. Yeah, that's the chapter 2 of this manga. Exciting shit, huh? Can't wait to have that drawn and translated.
No, we want to read something where a flawed hero with a tragic back story rushes in and sprays bullet and teaches everyone inside that they should be more careful about who they hang around with, while NOT getting killed himself, which was probably why he didn't stop and ask anyone if they did anything bad recently. I mean, he was outnumbered like 100 to 1.
Hell, for that matter. What if other guys in that room was innocent too. What if that corpse in the corner was someone doing a part time work serving Hors d'oeuvre to these fancy assholes? He had dreams, man. He was going to graduate college and support his mom, dude. But no one cares because he didn't have a nice set of tits. See how stupid that sounds?
Author even set it up by having the brat talk off to the side, declaring his dastardly intent to use her as a meatshield. That's some cheesy foreshadowing shit. Subtle as a hammer. So the assassin busts in and he's got like maybe half a second to mark everyone and take'em all out in a spray of bullet, and the evil little shit of a brat pulls her over him at the last split second to save himself. You see, that's a literary device to make him look even more EVIL. You're supposed to see that and think. "Oh, man, when I thought he couldn't be any slimier, he does that..."
But you managed to go off on a tangent that somehow this was a "good guy" (hint: good guys don't go on an extra-judicial killing spree) who should have known in that split second that she was someone innocent (I mean, who else was innocent? What about Harry the floor cleaner dude who had to stay late to wipe up vomit?) in that den of depravity?
What are you, 10?