I dunno if we can say it romanticizes crime and murder as sexy or anything else, because if that were the case, then we'd have to say that about every single television show, film, and piece of literature that contains any form of crime or violence. Some of my favorite films are very violent and I don't believe murder in real life is okay.
Honestly, I can see why they're joking about it on twitter cause like I mentioned in a previous post he unrealistically stabbed someone in the neck with extremely blunt chopsticks. It's totally absurd looking. Creative I guess, but absurd. At least they had the decency to give him a gun in the final scene that can still fire after being in water, and not the revolver from the Daechwita video. I would have ruined my stomach laughing if he'd pulled the revolver out of the barrel. (And don't even get me started on how he can't handle the kickback from a gun, and it's really hilarious looking).