Mikasa wasn't sure red was her favorite color so much as it just happened to coincide with many things she loved—her scarf, the flush of Eren's skin when they were alone, the autumn season when apples began to expire. She loved when Eren's lips turned dark red from too many kisses and bites, when he left maroon bruises on the inside of her thigh to be accompanied by ruby red marks at the base of her neck, always hidden beneath her tightly wound scarf.
A color with so much positivity should bring nothing but joy and yet, paradoxically, the deep shade of red that could only mean blood follows her in a way that brings nothing but misery. She's seen, tasted, felt more blood than she ever thought possible; sometimes, red reminds her of her parents, of lost comrades and of a little girl who didn't have the protection of a red scarf.
Red also reminds her she's an average human—an average woman—and every month when the red that blooms from within her comes, she's comforted by the normality and familiarity that there is some type of odd, reliable consistency in her life. That isn't to say she enjoys it—there's nothing comforting about a persistent ache that follows her and pains in her stomach that worsen the hunger she already has, but it is, at least, nothing if not a small bit of the average life she never particularly got to experience.
Sometimes, she gets so wrapped up in missions, in managing her strained relationship with Eren and training herself that she does not stop to realize when things are missing until someone else makes a comment. This time, it is Armin who reminds her after a day of training with him and Eren, for as he glances into the sky's sunset he says, "The sun seems like it's setting late today."
As she's wondering if it's even possible for the sun to run late, a particular word sticks out: late.
She's late, she realizes; her movements come to a halt and both Eren and Armin turn to look at her, Armin's eyes narrowed and Eren's head cocked.
This is how she discovers she can also love the color yellow. She learns she can love the color of the sun, the way bright golden flowers shine beneath it, and the way yellow represents the gender of a child she does not yet know.
Gifts in the color of yellow trickle in from friends despite her reluctance to take them. Her and Eren receive hand-knitted scarves and shoes, jackets, and outfits that seem impossibly small. She is grateful for their help and tries to express it as best she can with words of thanks at every gift but soon finds she has nowhere to store such precious items and neither does Eren. Their lives are not designed to support a child, let alone its possessions.
It's Armin who uses the last of his saved coins to buy her a second-hand chest decorated plainly with nothing but a large, yellow sunflower painted on with such care that she loves it instantly. She spends an hour after receiving it folding the knitted clothes and, when he isn't looking, refolding the pieces that Eren attempts to help her with.
They're scolded and reprimanded, of course, from every superior possible. Although it is never explicitly said to her, she feels the word failure follow her around like a dark shadow on her back, leeching off when she isn't actively trying to fend it off. She can't continue as a soldier and it is a fact that everyone is instantly aware of. When good-willed gestures are offered from friends ("Let me carry that for you!" "Do you need an escort? It's getting dark!") she finds herself growing more and more irritated: she's pregnant, not maimed or unable to care for herself.
Perhaps the worst blow of all comes when, upon wearing her gear one day, Levi tells her to remove it and put it away. With clarity and no hesitation he tells her, "You're dismissed from wearing it until further notice."
She has no desire to quit the corps and says as much—"I plan on wearing it as soon as I am able to once more."
The survey corps needs her as much as she needs it, just as much as Eren needs her to be there for him and vice versa. She will, in due time, put the gear back on and although there are still logistics to work out—who will watch their child when they're gone?—this is something to be dealt with later. A child, she decides one night when she is too restless to sleep, will not hinder her from helping Eren and nor will it prevent her from any of her own goals.
As months pass by, Mikasa finds she misses red less and less and takes solace in the yellow the earth has to offer. She sits beneath the sun on tops of grassy hills, surrounded by dandelions and sunflowers, where she can (most enviously) watch Eren continue to train and practice. On particularly warm days, she lifts up her shirt a bit, tucks it beneath her breasts to expose her stomach to the sky: she likes to imagine she's warming up the baby's home a bit like bread waking and rising comfortingly to the fire around it. It's on one of these days she dozes, her arm tossed lazily over her eyes for shade, when she feels rough, chapped lips on her stomach that startle her. The lips slowly graze the bump that, by her guess, is around three or four months and is noticeable but only just.
"Sleep well?" Eren asks, crossing his legs and arching his back. She notes with a tinge of envy the sweat that covers him, indicating a particularly good work out.
"I'd sleep better if I didn't feel so useless during the day." He doesn't remind her that sometimes she does do other important things—helping file paperwork, overseeing other trainees and helping perfect their form from the ground—and she doesn't bring it up. She feels useless doing anything but being in the air with him and Armin but knows well enough that even if she were to put on her gear and attempt to use it, she would have the support of none around her and would certainly only be fighting against a battle she stood no chance in winning.
"It won't last forever," Eren gently reminds her, pulling out strands of grass from beneath him. He looks up at her face, eyes still drowsy from sleep, and tentatively opens up his arms for her; she feels the relief in his body when she curls into him beneath the sun, his body already hot and hers warm from earlier.
"I hope we're not cooking the baby," she murmurs into his neck, her eyes drifting closed as she feels him pick her up to no doubt take her to her bed.
It is many more months until she once again sees red and she finds it reassuring in a small way that the process begins to happen in her favorite yellow sundress, made for her by a local woman town that had felt sympathy to see the young, pregnant soldier struggling in clothes that were too tight. She had only requested to see the child when he or she was born and offered to make the child clothes from the same dress when it would be too large and loose for its mother.
When she finally sees red come from her once more, it is not in a comforting or reassuring way; nor is it in a way of misery or terror that she's accustomed to. Instead, when red pools and blooms from her, she knows it is because she is—like she always has been, always will be—a female human, one that can give life like any other who chooses to do so. The red that comes from her this time signifies not death but life and for once she is scared of this color and what it will bring her.
Eren is there, of course, holding her hand and attempting to be as supportive as can be, offering words of encouragement and endearment; despite this, there is little more she wants to do than to tell him to be quiet and let her concentrate because, as she discovers, it is not as easy as one, two, three, push! She has to remind herself he is just as new at the entire process as she is and knows even less than she of what is happening to her body.
When the red ebbs and she's left with a tiny, wailing body and Eren over her shoulder, she's startled to see such large, green eyes on such a little face. She holds the tiny child closer to her chest, lets the baby feel her beating heart to momentarily soothe the crying. It's true, she thinks with tired amusement, that she loves red and yellow, but perhaps she loves green just a little bit more.