There's a second, more sinister parasite to worry about when talking about Quiet.
The next point of interest is her second parasite affliction. Quiet cannot speak because she's infected with multiple strains of the vocal cord parasite. Most of these are cured via the sterilizing Wolbachia vaccine, but Quiet also hosts the English strain, which may be a mutated strain immune to the treatment. The activated vocal cord parasites kill the host by feeding on the lungs, which then scar over and cannot be used to breathe properly. She doesn't have to worry about this personally though, as her previously scorched lungs are useless to her: Quiet can breathe through her skin, remember?
Quiet is one of Cipher's means of attacking Diamond Dogs, but because of Venom Snake's kindness towards her, she refuses to speak English to her captives, even after repeated bouts of torture. This is another plot point people are confused about. Why doesn't she just communicate the situation to them in means other than talking? Yeah, that would go over real well for Quiet:
“Hey guys, I'm a Cipher agent who's special circumstances may somewhat circumvent the deadly aspect of the vocal cord parasites. I willingly came to this base as a host of the English strain in order to infect you all, but because I have a crush on your boss I've vowed to never speak English again. It's totally the real thing, there's no chance of me becoming disenchanted with Venom Snake and wiping all of you out with a few deadly words, and there's totally no chance I'll ever slip over over the years and let loose some English. Now that I've told you my horrible secret, please don't do the smart, reasonable thing of killing me and incinerating my body to get rid of the greatest threat posed to your organization or the world in general.” –What people think Quiet should have said.
Miller would have had her shot and three-quarters of the way into the incinerator before she could finish saying “English strain.” She did the smart thing by remaining mute on the entire subject.
This is actually preferable to the alternative for Quiet, and it shows just how strong she is.
When you look at the whole picture, Quiet's scantily clad design is a great choice. She has a legitimate reason for looking like that. She was burned alive, rendering her lungs useless. Since her lungs are useless, she's a perfect vector through which to spread the vocal cord parasites. Her being this vector is the driving force behind her character and shows her strength by resisting torture out of loyalty to Venom Snake. That's actually great story planning.
Unfortunately, living without lungs is an impossibility without some magical MGS pseudoscience bullshit. To that end, she has The Ends's parasites to keep her alive via breathing through her skin. It's not a cheap excuse to have her half-naked, as they clearly put a lot of thought into the limitations of breathing through the skin. It's this purpose and effort put in that proves Quiet to be a true antithesis to sexy-just-because female characters.
Does the fan service hurt this point? In the eyes of many, yes, Quiet really didn't need to have her little rain dance scenes. There's a cultural difference at work here, though, as fan service is as common as water in Japanese media. It's not treated as that big of a deal. Just because you personally don't like something, does that mean it shouldn't exist? Maybe that nudge and wink wasn't for you. One of society's largest problem is that everyone's too self-centered to care about how someone else feels about a topic.
They went a little overboard with the fan service, big whoop.
Fan service doesn't erase the fact that Quiet is a strong, well-written character that doesn't need a man to save her. That puts her on a level comparable to The Boss, who was the most impressive female character to ever grace a video game.
Quiet before she had to be "scanty to live."
Simply put, Quiet's dressed as scantily clad as she is because she breathes through her skin. She's been treated with the upgraded version of the parasite that gave The End his photosynthesis powers. This is exactly the point where most people, like Jim Sterling, go off the rails and assume that since The End wore a full body ghillie suit, it doesn't make sense for Quiet to be almost completely naked in order to breathe and use her photosynthesis abilities.
Quiet has different circumstances, though. She was treated with the parasite to keep her alive. Within the opening cutscenes she's burned severely, with the inside of her lungs being scorched. If not for the parasite, Quiet would not be able to breathe period, unlike The End who has a fully functional pair of lungs.
Let's take a moment to introduce a little science. Quiet breathes through the surface area of her skin, meaning she has much less than 2m^2 of surface areas with which to take up oxygen. Care to guess how much surface area the aveoli of the average adult's lungs? 70M^2. The End wasn't running around naked because he could get more than 35 times the amount of oxygen Quiet gets, thanks to his functioning set of lungs.
This is why Quiet's lungs are useless.
Another nice touch, is that virtually all of Quiet's actions revolve around the anaerobic energy systems of the human body. She doesn't walk around with Snake because her low oxygen intake doesn't let her. When she does any sort of moving between distances, it's done as a short, super powered sprint. Other than that, she remains stationary. As you can see, a lot of thought was put into the “breathing through her skin” aspect of Quiet.
Why even put her in that situation, though? Probably because it fits perfectly into the story. The problem here is that a lot of people missed out on a large portion of said story. Many will even say MGSV:TPP has the worst story in the series, but that's because of the way it's told. I'll go out on a limb here and say that if the presentation were better, and the story wasn't locked behind secrets and hours of tapes that people missed or refused to listen to, the consensus would be that this entry has one of the best planned stories in the Metal Gear series.
Quiet was a former Cipher assassin who was set ablaze by Ishmael, her true target, while trying to eliminate Ahab, a witness that saw her face. Quiet probably knows the truth behind Punished Venom Snake (Coolest name in the whole damn series by the way). She recognized him as a witness and not her target even after his plastic surgery, and she was there while the doctor was explaining it to him.
Quiet is subsequently defeated in a battle by Venom Snake in Afghanistan and shown mercy, treated like a human being for the only time we'll ever see. Cipher saw her as a weapon, Miller saw her as a monster, and Ocelot saw her as an awesome science experiment and asset. Punished Snake saw her as human, and treated her that way. You have a traumatic event, Lima Syndrome, Stockholm Syndrome, and the fact that she shares a foxhole with Venom Snake (you have to cap out their bond to get the whole story), the most saintly character in the entire Metal Gear series. It's hard for me to see how everyone thinks her love for Venom Snake comes out of nowhere. Be it coping mechanism or the real deal, it's obviously there.
A warning before we begin: I'm going to spoil pretty much every major plot point for Metal gear Solid V: The Phantom Pain. Play the game before reading, unless plot-destroying spoilers don't bother you.
Metal Gear Solid V: The Phantom Pain is out, and to many it's a mixed bag of amazing. While the gameplay is nothing short of immaculate, many dislike the narrative structure, and the game is objectively incomplete. The entirety of the final chapter was hacked away from the game, likely due to the Kojima vs. Konami affair. Given the air of finality surrounding MGSV:TPP, those loose ends do nothing but leave a bad taste in the mouth that will likely never go away.
However, the biggest point of controversy seems to be the badass sniper Quiet and the way she's dressed. Yes, she's wearing a skimpy outfit, but it does have an explanation. Many people aren't buying it, though. Jim Sterling is an example, lambasting Kojima in one of his recent Jimquisitions. Kojima may have gone a bit far when he said “once you recognize the secret reason for her exposure, you will feel ashamed of your words & deeds.“ But I think those who are roasting him over the entirety of Quiet's design haven't looked at the whole picture.
Spoiler Dog, guarding spoilers ahead.
