If you look back to all the scenes where Sinon fights monsters, she's never smiling. Everyone says she's strong, but she never "enjoys" her fights per se. You could argue that she let out her breath after fighting the monster boss because of sniping technique... or because she was tense. Given what happened this episode (comments about smiling, less realism than expected), I'd give the latter more weight. That's the significance of the smiling bodyguard. He's strong enough that he can smile on the battlefield. Sinon thought that if she could defeat someone like that, perhaps she'll be able to feel confident and enjoy her fights as well.Originally Posted by lelouch
In regards to "Why did Sinon run after she missed", the guy commented before about providing Sinon 60 seconds to re-ID the opponent or something if she missed. That means missing a shot has penalties. I'm going to hypothesise that it has to do with bullet trajectories. I think it could be one of two mechanics:
1) If someone is looking in the general direction of you, they can see your shot trajectory. However, if you scope them long enough to "ID" them, then the game turns that off, as if to say that you have the jump on that guy. This goes away if you miss or if you re-locate, which takes an extra 60 seconds.
2) In general, people can't spot bullets unless they're "engaged" in a firefight. That means being shot at and surviving it. To sear off your "engaged" status, you'll have to hide out of sight for 60 seconds.
That would be what makes Sinon a great sniper: close to 100% accuracy. Because if you're sniping and you miss/give your position away, your efficacy goes way down.
As for her combating the boss monster and it just standing there, maybe she's taking it on outside of its engagement range. She's able to get shots off at it due to her gun/skill, while the monster isn't able to engage since it can't see/detect her due to either stealth, or engagement distance/mechanics.
Given that this is VR, dying might be a more daunting experience than having GAME OVER printed over your screen. Pain was reproduced in SAO, it might happen here. Imagine that the gun sounds, the earth and the atmosphere all feel real, with the only difference being that when you die, you actually don't. If you're only worried about the consequence of dying then it's no big deal. However, I'd say that the experience of dying for the most part is scarier than the consequence (after all, who knows what the consequence is besides you stop moving..).