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Chapter Text

When Shiro walks into Keith’s room he’s not expecting to see the man on the bed, back against the wall, shirtless, squeezing rhythmically at a small plastic device that’s suction cupped to the breast. The bottle attached to it is filling rapidly with- 

Keith stiffens and his hand tightens on the nozzle, causing him to yelp. He freezes. Eyes blown wide. 

Shiro can’t move either. If he didn’t realize it before, a tiny stream of white begins trickling down from Keith’s other nipple. 

Keith looks away and slowly releases his grip with a hiss and the bottle gains more liquid. 

”Keith, are you-” he finds his voice through great labor, ”Are you lactating?” 

The hand not holding the pump grabs for the blanket pooled at his waist and raises it to collarbone. Shiro has the feeling that Keith wants to bolt but he was in the middle of milking and the better option would be to hide. Shiro himself feels like running. 

”I...” he begins and there’s movement beneath the blanket until both arms emerge to hold it tight to his body. 

The low hum of electricity and engine of the ship sounds loud in the pause. 

Sweaty hair clings to Keith’s forehead, it’s messed in all different directions. His breathing is heavy, audible. Across the bridge of his nose and cheeks the skin is flushed red. When he continues his voice is quiet and raspy, ”It’s been doing this for a few months. I’m not sure why. It just hurts if I don’t pump.” He looks away from Shiro and to the wall. 

”I’m sorry.” Shiro wants to bang his head against the wall for walking in on Keith. Especially walking in on something so... intimate. Something Keith seems embarassed over. ”It’s perfectly natural. Well, I mean lactating is. Natural.” Fuck. 

Keith scrunches his nose and chews at his lip. ”Shiro, please. It hurts.” 

If he weren’t feeling awkward already, Keith’s words would have done him in. To carry feelings for Keith so long, to have imagined so much, too much, things well beyond the appropriateness of friendship, and hear those words spill from Keith’s mouth, hoarse and teetering on the edge of desperation, it has Shiro feeling hot. His blood is burning in his veins. Please? Please what? He wants to say he’ll do anything. Wants to hope Keith means something less than decent. 

”What do you need?” 

Keith’s face erupts with fire. ”I wasn’t going to pump right now but I’m really full. Can- I have another pump in the top drawer- Can you help me?” 

Not trusting himself to speak, to acquires the pump and sits down on the bed. 

Refusing to meet his gaze, Keith lets go of the blanket and places the half-full pump back on his chest. Shiro watches the milk slosh a bit in the bottle and has to choke down the craving for it. They haven’t had any food or drink from Earth in so long and there it was, a bottle of milk, freshly produced, human or otherwise. He swallowed thick and tried to focus on attaching the other pump. 

”You’ve gotta latch it right or it’s going to hurt.” Keith guides Shiro in placing the suction over the nipple. A nipple that’s puffy and deep brown and straining and leaking droplets of white. 

He tests the latch by squeezing the handle and a low moan along with milk is expressed from Keith. 

”That ok?”

Keith just nods. 

The only sounds in the room now are the pumps, their breathing, and the strained noises of pleasurable relief that seem to slip from Keith against his will. It doesn’t take long for the bottles to fill. 

When the pumps are removed, his nipples are left swollen and red from the friction and glistening wet from the milk they just made. 

”Thanks, Shiro. Can you set these on the table? I’ll clean them out later.” Keith sinks down into the pillows looking spent and exhausted. 

”I’ll clean them.” 

”Ok.” Keith waves at him and wastes no time curling on his sides and settling into the bed. 


Shiro takes the bottles to his room, lucky to avoid running into anyone else. He takes them to the sink and unscrews the lids but his hands betray him and raise them to his lips. He gulps down the milk greedily. It’s warm and sweet, far sweeter than cow’s milk. He hates himself but he polished off both of them. 


Two things had just happened. 

One, he’d learned his friend was lactating.

But two?

Two was the real kicker. Or maybe it was three things? 

His friend was making milk and it was sweet and drinking it felt like having a comfort from Earth. 

Only now he wanted to drink it straight from Keith. 

Shiro wanted to nurse.

Chapter Text

”Man, what I’d give for a nice tall glass of milk,” Lance whines as he brings his food goop to the table. He sets it down and falls gracelessly into the booth-style chair. 

Pidge hums her agreement.

Hunk scoffs, ”As if I’d let you just drink it. Man, there are so many recipes I wanna make but they all need milk.” 

Shiro looks over to Keith from the courner of his vision. Keith is stiffly hunched over his bowl of goo. Keith shifts in his seat. They haven’t spoken about what happened, or at all, really. The last they saw each other alone was when he returned the washed bottles and he’d felt too guilty to say anything to Keith then. He had, after all, drank Keith’s milk. Not milk he owned. Milk that came from him. 

”Ok, sure everyone, jump on the train, but I’m getting a glass if we ever track some down. Sorry not sorry, Hunk.” 

”Can we shut up about milk?” Keith slams his fists on the table and storms out of the room. 

Lance gestures at the door, ”The hell is his problem?” 


The hallways are quiet, all the noise of the others stays inside the kitchen. He’s not sure what he wants to say to Keith. He’s not sure what Keith wants him to say. There’s not much that throws Shiro off, makes him stammer, makes him uncertain, or even afraid, at least not that he’d admit, but this definitely has him mentally stumbling. 

He’s noticed Keith for awhile now. 

The man has really grown into himself; he’s long limbs and strong muscles and a sharp but beautiful face. He’s far shorter than Shiro, but that makes it all the more breathtaking when Shiro’s knocked on his ass when training with Keith. The few times he’s pinned Keith, mostly because it’s hard for Shiro to allow himself to really wail at Keith, he’s felt the adrenaline pump through his veins and a heat pool low in his stomach, and he’s been all too glad when Keith rolls them over and hops to his feet. 

He stops at Keith’s room with his fist raised to knock. He’s still unsure what to say. ”Keith,” he announces this time, along with a knock, because this whole mess could have been avoided if he’d done it before. ”Can I come in?” 

”I’m fine, Shiro.” Keith calls from the other side of the door. 

”Keith, please? I think we should talk about this.” He lets his head thunk soft against the door. It’s a cool metal. Sterile. A reminder that they’re flying in space, far, far away from Earth. 

”There’s nothing to talk about!” 


There’s noise behind and the door and then it’s opened suddenly, leaving him to stumble a bit inside and it shuts automatically behind him.

Keith stands with his arms crossed. He’s shed his armour and the only clothing he’s wearing is their skin-tight undersuit. It shapes over and around Keith’s breasts, which have grown to at least a palm-full, and pert, full nipples. There’s a small wet spot on the fabric over the right side. 

How’d he not notice this for this long?

”What?” Keith raises his arms to cover his chest. 

”I- Keith. About earlier-”

”-It’s nothing. I told you-”

”-You walked out, though. I just figured that maybe this,” he gestures vaguely, unwilling to call it for what it is, ”is weighing on you. And maybe it would help to talk?” 

Keith sighs and sets down at the chair at his desk. ”What’s there to talk about? Just one day I woke up, felt... full, and yeah. Now I’m just... like this.” 

Shiro walks to the bed and sits. He doesn’t want Keith to feel cournered or like Shiro is hovering. He decides to wait. To let Keith gather himself. 

”I went to the sick bay and Coran scanned me. And it’s apparently normal. Normal for-” he sucks in a breath, ”-someone like me. Maybe this is normal but me? I’m not normal.” 

”Is this about being half-galra? Because Keith that’s nothing to be ashamed about. You can’t measure yourself against others like this.” 

Keith flies out his chair and spreads his arms wide, nearly snarling as he speaks, ”Nothing to be ashamed about? Shiro, you don’t get it! I can get pregnant! I’m a guy, why the hell can I get pregnant? And- and my stupid body is doing this. I’m nothing but ashamed.” He’s in frustrated tears. 

Shiro stands and carefully approaches Keith with a hand extended. He waits, hand just over Keith’s shoulder, and searches Keith’s eyes for affirmation. At Keith’s nod he grasps the man’s shoulder and squeezes. There will be time enough for Shiro to process it and to be shocked, when he’s alone, and Keith isn’t before him crying. 

”There’s nothing to be ashamed about. It’s ok that you’re different, Keith. But I hear you. It’s hard to be different. It’s scary. But we’re here for you- I’m here for you.” 

Keith smiles through tears, ”Thanks, Shiro.” 


The rest of the day goes fairly typical. They all train. They eat together. Lance and the others think it’s just Keith being Keith and for once Shiro is glad that they don’t understand Keith like he does; it’s simpler that they think Keith just has a childish temper. 

It’s typical at least until Keith knocks at his door in the evening. 

”Keith? Come in.” He ushers Keith in. 

”Shiro... Can I ask you something? I can’t- My pumps, they’re missing,” Keith is wringing his hands and staring down at the floor. ”I’ve tried ignoring it but,” he grimaces, ”Shiro, it hurts so bad. I’m not good at hand expressing yet. Listen I know it’s a lot to ask but-”

Shiro inhales sharp. He hopes Keith doesn’t hear it. He hopes he doesn’t see it. Doesn’t see what Shiro feels in himself; eyes unfocus, probably blown wide, mouth agape as his breath begins to labour, and a stiffening of his posture, as well as other things. 

”I don’t think you know how to express either- I, uh, Shiro. Can you... Would you help me?” 

His voice breaks as does his resolve to keep calm, to reject Keith, knowing he’s not going to be able to keep his desire secret if he doesn’t, ”Of course.” 


Keith reaches behind and unzips the suit. He peels it down his torso and it falls just  above where his happy trail dips down. He turns around and climbs on the bed, butting his back against the wall. His eyes are vulnerable. 

Shiro moves slow to the bed and rests on his side draped over Keith’s lap. His breath must ghost across Keith’s chest, which is likely sensitive, because Keith shivers. 

Keith guides Shiro by a hand cradled to the back of his head, ”Don’t suck hard until we get the latch, please,” his eyes slip closed and he sighs as Shiro’s mouth closes around a nipple. 

As instructed, Shiro suckles lightly until Keith gives him the go-ahead though the droplet of milk that slides down his tongue is affirmation enough. It’s warm, just like he remembered it was, only it’s warmer than from the bottle since it’s fresh from Keith. And sweet. It’s like honey had been stirred into a glass of milk, only he’s surrounded by Keith in all his senses. From the heat of where Shiro’s touching Keith’s skin, to the intoxicating scent of Keith and Keith’s soap, to gentle petting of his hair by long fingers, it’s all Keith. 

He drinks in the gasps and pleased sighs that Keith is making. 

”Shiro.” It’s a whisper and seems like it uttered without realization. 

Shiro massages the nipple with his tongue as the milk is starting to run dry. 

Keith hisses and drags Shiro away by the hair, ”Sensitive,” he pushes Shiro to the other breast. 

Shiro groans and latches quick. 

He massages the drained breast and it’s noticeable by feeling how swollen Keith was with milk. Shiro thinks he’s beginning to understand the desperation. 

He’s disappointed when Keith has no more milk to give but he does his best to pretend otherwise. 

”Feel better?” 

Keith replies breathless, ”Ya.” 

Shiro sits up and it’s dizzying. Though having the blood rush to his head takes it from other parts and that’s appreciated. He notices, though pretends not to, that Keith himself is feeling the same type of heat. It could just be a biological reaction so Shiro doesn’t think into it. 

”Thanks, Shiro.” Keith smiles but can’t meet his gaze. ”I’m exhausted. So, uhm. See you tomorrow.” 

Shiro rolls on the bed so that Keith can get up. Keith wastes little time zipping up and heading out the door. 

Shiro just stares as it closes. 

Despite all he falls into self-passion to ease the ache of his own before he falls asleep. The taste of Keith’s milk on his tongue makes him cry out into the pillow. He’s glad his room is at the end of the hall.

Chapter Text

”Don’t whine, please,” Keith asks quietly. They’re not in uniform today and the nursing bra he had been using is in the wash. There’s nothing between his nipples and the thin fabric of his shirt. If he leaks, everyone’s going to see it. 

”Yeah, well, Mr. Awesome, we can’t all be just perfect like you,” Lance jabs a finger directly in the center of Keith’s chest, his voice no less whiney despite the request. The finger just barely misses the soft tissue of either breast and it makes Keith inhale sharply. 

”I’m not though.” 

”You’re...Oh my god,” Lance huffs and changes his voice as if to imitate Keith, ””My name is Keith and I’m not good at anything ever, I’m just so bad-” the pitch of his voice is getting to Keith, whom feels the flutter and subsequent warmth fill his chest, but he’s terrified of moving. 

Lance continues to rant and Keith stays still. It’s too late, the milk has let down, and his only chance of sneaking out without suspicion is to let Lance have his go. 

Breathing slow through his nose, he’s doing everything to keep his shirt from rubbing. He just needs the milk to stay in. If doesn’t move, doesn’t create friction, maybe-

Lance shoves him. 

Both palms out flat exactly where Keith didn’t want them. 

He stumbles back a few steps but the real horror is the fabric he feels soaking. 

”Keith?” Lance’s eyes have landed on the wet spots. 

He’s so fucked. 

”It’s nothing,” his arms fly up to cover his chest. He wants to run, badly, but his legs are frozen. 

”Keith, are you-” it’s soft and Keith hates hearing it.

”It’s nothing!” He shouts. 

”Keith, it’s ok, I’ve had sisters-”

”Stop!” Keith regains control of his limbs and shoves Lance away. He dashes quick and blind to his room. Of all the people to find out it had to be Lance. 

The whole ship will know by evening. 

Of all the days for Shiro to be out on a mission...


Keith waits for knocks on his door, or loud voices discussing something, but it never comes. What does come is his name, and a request that he open the door. He would ignore it but he knows Lance is not one to let things go. 


Lance’s face flushes as he sneaks a glance down. If Keith looks as swollen as he feels, he can understand Lance’s embarassment. ”Hey, uh. I’m sorry about earlier. I- Well I wanted to see if, I mean, ok. Listen. I’ve read a lot about this and I heard that it can be painful.” 

He exaggerates a breath and continues, ”I’d found pumps the other day, and I didn’t know they were yours. I figured we’d somehow collected them from somewhere, y’know, ’cus we get a lotta junk. Uh, anyways. I... threw them out. So, I’m sorry about that but also I wanted to make surr your didn’t need amy help.” 

Keith gulps. This is Lance. But also he’s aching. Badly. 

”I- don’t take it wrong, y’know? I just know a bit about it so, like. I’d be able to help, at least since your pumps are now gone.” 

Shiro isn’t due back for another few days. Hand expressing is still tricky for Keith, too, and his hands cramp up well before he’s fully drained. Lance, at least, seems sincere in his apology and willingness to help. ”Fine.” As if he can think over the ache. He doesn’t bother. 

Keith bites the inside of cheek hard and his shaking hands raise his shirt up and off his body. He feels naked before Lance. His nipples are drooling milk and his breasts feel like they’re going to break away from his chest with their swell and fill. He looks anywhere but at Lance as he assumes the position on the bed. 

”It’s ok, Keith. This is natural,” the words are the same ones Shiro gave him and he hates that they make him relax, allow him to watch Lance as the man settles across his lap and meets his gaze. A gaze he maintains as his lips encompass a puffy, weeping nipple. 

Keith loses his breath as he watches Lance take the first, firm suckle. The latch is perfect. It forces a groan from Keith. He closes his eyes and still can see the intense blue of Lance’s that refused to avert, even as breast came into mouth. 

He hates it. It feels so good.

Lance suckles Keith and makes good on his promise that he knew what he’s doing. The steady pull and release of the suction draws a gapless stream from Keith and it’s a fire from head to toe from how blissful it feels, how relieving, and comforting. 

He can’t help the hand that moves to cradle at Lance’s neck. 

Lance’s mouth is so warm and wet and velvety and his nipples flow milk easier than they ever have before. 

”Lance,” he can’t contain the name on his tongue. He’s nothing but the point where he meets Lance. Except for the need growing lower. 

When Lance has fully drained one breast, he kisses butterfly like to the nipple at its peak before readjusting to the other side. The next latch is just as skillful, feels just a heavenly. 

”Lance,” it’s a prayer now. 

His mouth worships Keith for his milk, lapping and suckling greedily. This time there’s more fervor to the action and milk spills down his chin and to Keith’s stomach, he’s working Keith faster than he can swallow. 

Keith shuts his eyes tightly riding the pleasure as he’s drained until he’s dry and Lance sucking hard, too hard, trying to draw more from Keith than he’s made. He whines and pulls Lance off by his hair. 

”Sorry,” Lance smiles at his sheepish, chin glistening. 

Keith’s mouth feels as dry as his breasts. 

”You good?”

Keith nods.

”I’m glad,” Lance chuckles like it’s normal to have a good a laugh after nursing your friend. Like he hadn’t seen to need in Keith’s pants. 

Keith nods.

Lance gives one kiss each to both nipples and hauls himself up from the bed. ”Sleep well, ok? If you need me, for anything, come get me.” His face goes red like he’s finally noticed the situation, but he leaves Keith with a wink and a wave. 


Chapter Text

When Hunk shows up in front of his door, Keith just knows it’s not gonna be good.

”If I give you my milk will you just leave me alone?” 

”Your... milk?”

”Don’t play dumb! I know Lance sent you. Look, just. Get me more pumps and I’ll give you the bottles-”

”-Keith, what are- Are you,” Hunk blanches and refuses eye contact, raising his hands over his chest and making a grabbing motion, ”Y’know.. uh...”

”..You really don’t know?”

”No, no. I hadn’t. But now I’m kind of curious. Do you think I could still... get some? I might be able to cook something. We haven’t had dairy in so long.”

Because absolutely what Keith wants is the entire castleship eating food made with... his own milk. ”I need those pumps though.” 

”Oh, sure. Yeah. Of course. I’ll see if we can’t find the nearest swap moon and stop there.” 

Keith nods, ”Ok. Night, Hunk.” He closes the door before Hunk can get any other ideas. He needs to go milk himself. 

Shiro is still a few days out from getting back to them.


It’s uncomfortable at this space mall. There are a few galra, or at least part-galra, they pass by and each one of them is eyeing Keith up and down. Their noses twitch and one of them licks their lips while looking right down at Keith’s chest. He’s loathe to admit that he smells the air around them. Immediately he feels let down. He crosses his arms over his chest. 

”C’mon, Hunk, let’s- let’s just go.” 

Even as they’re walking away, and thankfully that group lets them, he can still feel the hairs on his skin standing up and the scent lingers in his nose, intoxicating, making him want something without knowing what. 

”You ok, buddy?” Hunk whispers. 

”It’s whatever.” His breasts sure don’t think that with how close to leaking they are. 

Hunk manages to locate a maternity store. The clothing and overall appearance of the items are much more neutral than back on Earth. There are some dresses that have lace and frills and flowers, but others are plain, solid colors. 

”So,” Hunk begins as they’re wading down the clothing aisle to the baby food and feeding area, ”Do you know what caused, uh, this?” 

”The milk?” 

”Yeah, I mean. On Earth...” 

Keith scoffs, ”Yeah, well. In case you forgot, I’m not human. Not fully.” He glares at the rows of binkies if just because they’re there.

”Keith, I didn’t mean that. I just wanted to know if Coran has scanned you and if the lactation is normal.” 

”It’s... normal. We just don’t know why, yet.” 

They finally reach where the pumps area. It’s a bit of a dig to find ones his size; humans are a small species. When they check out Keith immediately tracks down a bathroom and fills two bottles. But just as he’s about to pour them down the sink, Hunk comes in and protests that Keith not waste it. With a grumble, Keith lets Hunk have one of the bottles. It’s strange watching a friend gulp down his milk but Hunk licks his lips afterwards and hums approval like it hit some spot. Which is both flattering and unnerving. 

The other bottle is promptly poured down the drain.


”Good news, Number 4! I was able to ask Ulaz about this whole ordeal between meetings,” oh god, of all the galra to know he’s lactating, Keith grunts internally, ”And he says it’s, what they refer to as, mating milk. How exciting! My boy, your body is just trying to help you with your courting.” 

Which is honestly much worse than Keith thought it would be. ”How do I get it to stop?” 

”My boy, it will come in cycles. You just have to pair. Chin up, though, you’re a strapping young lad, and you’re sure to land someone soon.” 

”Cycles? Wait, so, you’re telling me this isn’t going to stop?” 

”Well, not permanently, no, not unless you’re pairing regularly or else pregnant.” 

Keith feels his blood run cold, ”When you say pairing... you mean- You’re talking about... sex?” 

Coran guffaws and claps Keith on the shoulder. ”Right! Don’t fret, it’s natural and a part of galra life.” 

He thanks Coran quietly and excuses himself to his room. He needs space. He needs to think. 


”Here you go,” he gives Hunk a few bottles full of milk. 

”Thanks, man. I’m gonna make us something delicious!” 


Keith is walking into the dining hall, groggy from not getting get much sleep. Pidge is eating a big bowl of what looks like some type of fruit loops. And-

”Keith! Look! Hunk must have found milk on the swap moon yesterday. It’s... sweeter than regular milk. I want to run some tests on it, actually. See what wild, alien species produced it.” 

”Don’t!” He exclaims.

”Whatever, Mr. Prickly Pants, I’ve already set up a lab and it’s processing.” 

The cereal is gone and all that’s left is the milk. She raises the bowl to her lips and slurps the rest of it.