This is a mini-fill, written for part of this prompt in the norse!kink community LJ; originally written before Thor 2 was out, so it might not be TDW-compliant:
Jane, Thor and the W4 are on this adventure and they have to take Loki out of jail and drag him along because he could be helpful. But the W4 don't like Jane. She's very much the sort of person Loki was before he went insane. They don't have a problem with her being science/magic minded, because she's a woman, but that's balanced out by the fact that she's a mortal. Thor is just chuckling at some of the comments and missing the insults and generally Not Getting It. Loki, however, has seen this before. Loki, although handcuffed and constantly watched, is not putting with this sh*t. So he blatantly points it out every time they say something even faintly offensive toward Jane - who, like Loki once did, wasn't going to talk back at them for the sake of the peace and their apparent "friendship".
It starts almost as soon as their trip does. She refuses to see it at first, because cultural differences, right? Some leeway is to be expected. But every instance makes more difficult to deny that it is bothering her, and she switches to mentally chiding herself, 'Stop being so sensitive, Jane', whenever it happens; because after all she is the only one who notices.
Except she isn't.
She catches the looks Thor's brother's gives her almost from the beginning, but they are difficult to read, until they are not. She doesn't know how she can tell, because his face basically remains the same, but she can see the slowly building anger in his gaze. Whenever Sif says something derogatory to Jane, whenever Fandral or Volstagg are carelessly dismissive about her possible contributions and strengths, whenever Hogun acts as if her opinion isn't worth inquiring about, whenever Thor chuckles with them.
She isn't imagining things.
She is the only one who sees the pattern when things start to go pear-shaped for the others. They are little, inconsequential troubles: a log crackling and spurting sparks at Volstagg whenever he gets close to that night's meal, a little magpie following Hogun around and trying to make a nest in his head, Sif's whetstone going missing three nights in a row, Fandral's beard developing some strange black spots that clash horribly with its owner's image.
Everybody blames Loki right away, but it is not hard for Jane to realize that yes, she's the only one that sees the pattern. And it is not even that Loki is discreet; he was, at the beginning, but eventually it becomes so in-your-face that as soon as one of the others says or does something derogatory to Jane, he retaliates.
And she doesn't want to feel grateful for it, because he's Thor's evil little brother.
But she's getting tired of being dragged around and being glared and sighed at when she can't keep up with the rest of their group, so there's no complain from her part when Loki gets out of the road and sits on a rock and refuses to move, forcing the others to camp in the site despite their original plan to walk for many more hours.
And she's getting tired of being left behind to set the camp and build the fire and being glared at when she can do none of it right because she's a city girl dammit and how the hell is she supposed to know how to set up an Asgardian tent if they don't come with instructions, so she only blinks innocently when her tiny collection of twigs turns into a small mountain of branches that bursts into multicolored flames capable of putting to shame anything ever seen on Burning Man.
And if she has to sit around every night to hear about another battle or hunt or mighty adventure while her own stories (she's the only women currently in her particular subfield, dammit, she's fought more battles and achieved more things in her life than any of them) are brushed aside with a pitying smile, then she refuses to feel ashamed when a smile of her own escapes as the roasting deer they are yet to eat turns into a million butterflies and flies away.
And she refuses to sit back when the scowls and snide comments and chidings Loki has been increasingly receiving escalate all of a sudden, and Thor all but drags him away by the neck.
Thor doesn't have a quiet voice, so she can't not listen to the accusations he spits, Loki won't you learn, Loki how can you, after all I've done for you, after they agreed to accept you back.
"He wouldn't have to do anything if you dared defend me!" she all but yells as soon as she reaches them, incensed, because as much as she refused to admit it, that had been what hurt most.
And Thor, dear Thor, turns to look at her obviously surprised both by her and by what she said. His face is a big innocent What, and she almost takes her words back, but he's still forcibly holding his brother by the neck against the trunk of a tree, and how did this end being her life.
Dear, stupid Thor.
"I understand you have been their friend for longer that I've been alive," she starts, trying to explain without dropping on his head the ball of anger and despair and self-doubt that' been collecting in the pit of her stomach, "and I know you are their Prince, and unlike me they are your subjects as well as your shield brothers, and as such there's certain amount of respect you owe them. But you're supposed to be in a relationship with me! We are supposed to be equals!"
He jumps, and there's something angry in his eyes, but she doesn't allow him to speak.
"I'm not saying I want to be treated as a princess, I couldn't care less, but I am a person! Not something you dragged back home, some, some, some kind of pet, look how cute, she even thinks herself clever and civilized, here, praise her for that neat trick, and oh she's trained! She hasn't pissed in your shoes!"
She's confusing him, or, or something. She can see it clearly in his face, there is something here, but he still doesn't understand.
"No!" She has to make him see, otherwise she'll chicken out and never try to do this again. "You are Asgardian, yes, and I'm from Earth, from Midgard, and we are different, but you never made me feel our differences were important."
"Because they are not."
And he's so earnest, so sweet, that she wants to kiss him. But.
"Then why do you never interfere when I'm being insulted?"
He gets angry at that and his hold on Loki, having loosened, turns punishing. "By whom?" he asks with a booming voice, but she can tell to him the answer is clear.
"By your friends!" she yells as Loki's face turns a darker shade. "By Sif, and Fandral, and Volstagg, and Hogun!" she lists, knowing that Thor still wants to think of Loki as a friend, even if he's not exactly showing it now.
The honest surprise in his face hurts.
"All their words have always been in earnest," he says. "I'm sorry if you found them insulting."
"If I found them … Thor." Her heart is breaking, incredulous. "Are you telling me I invented the insults and slights? Are you saying they are, what, all in my imagination?"
And for some reason, instead of being taken aback in shame as she expects from one as free with his hearth as Thor is, there is both anger and fear in him.
"There is something here," she frowns, looking at Loki for a moment before looking back at Thor and finding both emotions even closer to the surface. "Let Loki go, this is only between the two of us."
And Thor does, but there's a painful and terribly false smile in his face that looks horribly out of place. "Sure, why not. He's already poisoned you against me."
Loki doesn't fall, even if he seems ready to. Instead he rolls his eyes, pushes himself with difficulty from the tree and stumbles with unsteady steps further into the forest, in the opposite direction of their camp.
She's not surprised this whole mess comes back to Loki, for however much Thor chooses to express his desire to have his brother and his beloved on friendly terms, she hasn't missed the way he doesn't trust Loki won't hurt any of them. He believes Loki would do it with the only purpose to hurt him, Thor, but lately she's been thinking Loki sees it more like a form of self-harm.
"He hasn't told me anything, Thor," she says tiredly. "He cannot speak, remember?"
"Loki won't allow such a small thing to stop him."
A small thing, when Thor and the Queen herself had remarked how much Loki valued his words.
So she takes both of Thor's hands between her own and waits until he gives her all of his attention. "Thor, you're scaring me. This isn't you. There's something here I'm failing to understand, and I can't, I don't—"
"You are using his words," he declares, all anger and fear and despair. "He's put his words in your mouth and I don't know how."
"From when we fought."
And as far as Jane knows there are only two times in their long shared lives that Thor truly considers fights, and from the way he speaks of them on the few occasions he dares to, she would have believed that You're not my brother is the worst Loki could have ever told Thor.
Apparently she's wrong, if Loki ever said anything similar to what Jane has said.
And if Thor hasn't learnt at thing despite losing his brother to death and hatred over it, Jane is not sure she can manage better.