The mirror didn't lie. Izuku turned sideways, letting the morning light catch the sheer fabric of the babydoll—pale green threaded with pink, the hem brushing his thighs, the front panel split open to frame the heavy curve of his belly. Seven months. His body had never looked like this before, all soft curves and taut skin, breasts fuller than they'd ever been, nipples dark and swollen against the lace. He traced a hand down his stomach, felt the flutter of movement inside, and smiled. Two babies to take care of. Two sons who needed him. But today was about his firstborn.
The note was simple—bent in half on the kitchen counter where Katsuki would see it when he came down for breakfast. Come to Mommy's bedroom. I want a very special Mothet’s Day gift this year. Izuku's hand had trembled writing it, but his voice had been steady when he'd whispered the words aloud. Testing them. Claiming them.
He arranged himself on the bed, propped against the pillows, one leg bent to let the babydoll fall open and expose the pale skin of his inner thigh. The morning light painted everything gold. He'd left the curtains partly drawn, the room dim and intimate, smelling of the floral perfume he'd dabbed behind his ears and between his breasts. His cunt pulsed slightly beneath the fabric—a warm, familiar ache. He didn't touch himself. Not yet. This was a gift, and gifts needed to be unwrapped with ceremony.
The footsteps came sooner than he'd expected. Heavy. Hurried. A pause at the door, then the creak of it swinging open.
Katsuki stood in the doorway, still in his sleep pants, hair a wild mess of ash-blond spikes. His eyes found Izuku immediately, and something in them broke open—confusion and hunger and a desperate, childish relief. "Mom?" His voice cracked. "The note—"
"Read it right, baby boy?" Izuku's voice came out soft, honey-thick. He let his hand drift down his belly, fingers trailing along the hem of the babydoll. "Come here. I want to tell you what I want for Mother's Day."
Katsuki crossed the room in long strides, stopped at the edge of the bed, his chest heaving. Izuku reached up and caught his wrist, pulled him down until Katsuki's knees hit the mattress, until he was kneeling beside the swell of Izuku's belly, close enough to smell the perfume, the milk, the warmth of his mother's body.
"I don't want breakfast in bed," Izuku whispered, threading his fingers through Katsuki's hair. "I don't want flowers or cards or any of that nice, normal stuff." He tugged gently, guiding Katsuki's face closer to his stomach. "I want my baby boy inside me. All day. I want to feel you fuck your mommy's pussy until I can't walk straight. That's what I want for Mother's Day."
Katsuki's breath hitched. His hand came up, trembling, to press against Izuku's belly—feeling the warmth, the life, the barrier of his unborn sibling between him and what he wanted. "Mommy, I—" His voice broke. "Can I? Really?"
Izuku nodded, a slow, deliberate movement, his green eyes holding Katsuki's red ones with a heat that made the room feel smaller. "Yes, baby boy. That's exactly what Mommy wants. Your cock inside me. All day. I want to feel you stretching me open, filling me up, reminding me who I belong to." His hand slid down his belly, fingers trailing through the gap in the babydoll, dipping between his thighs. "Mommy's pussy is so wet for you, Kacchan. It's been dripping since I wrote that note."
Katsuki's breath came in sharp, shallow pulls, his hand still pressed against Izuku's belly, feeling the warmth, the life, the barrier of his unborn sibling. "Mommy, I—" He swallowed hard, his voice cracking. "I don't wanna hurt you. Or the baby."
"You won't." Izuku caught his son's hand and guided it lower, pressing Katsuki's palm against the soaked fabric of the babydoll, against the heat of his cunt. "Mommy's body knows what it needs. It needs you. It's been needing you since before you were even born, baby boy. This pussy made you. It remembers you. And it wants you back inside."
He shifted on the bed, spreading his legs wide, the sheer babydoll falling open to expose everything—his swollen belly, his wet cunt, his hard clit throbbing. Izuku hooked his hands behind his knees and pulled, showing off his flexibility, the way his body opened for his son like a gift being unwrapped. "Look at what Mommy saved for you. Look at your present."
His fingers found his own pussy lips and spread them apart, revealing the slick, glistening pink inside, the way his hole pulsed and clenched around nothing, drooling down onto the sheets. His clit was swollen, dark, desperate—jutting out from its hood like it was reaching for something. "See how wet I am, Kacchan? That's for you. Every drop. Mommy's been saving all of it for her baby boy."
Katsuki made a sound—high, broken, animal—and crawled up the bed on his knees, his sleep pants tented, a dark spot of pre-cum already soaking through the gray fabric. His hands trembled as they found Izuku's thighs, gripping the soft skin, pushing them wider apart. "Mommy, please—I need—I gotta—"
"I know what you need, baby." Izuku reached down and hooked his fingers into the waistband of Katsuki's sleep pants, pulling them down just enough to free his son's cock. It sprang out, thick and heavy, the head dark and slick with pre-cum, the shaft veined and pulsing. Izuku's mouth watered. His cunt clenched. "Fuck the pussy you were born from, Kacchan. Come home. Come back inside Mommy's wet cunt. Inside Mommy's warm womb. That's your real home, baby boy. It always has been."
Katsuki positioned himself between Izuku's spread legs, his cock nudging against the slick heat of his mother's entrance, not pushing inside yet—just pressing, teasing, feeling the warmth and wetness and the impossible reality of what he was about to do. His whole body shook. "Mommy, I—I love you. I love you so much. I'm sorry I was mean. I'm sorry I pushed you away. I just—I was so scared you wouldn't need me anymore."
Izuku's eyes burned. He reached up and cupped his son's face, thumb brushing away a tear he hadn't noticed falling. "Oh, baby boy. Nothing could ever replace you. You're my first. My best. My most important. And I'm never letting you go. Now—" He pressed his hips forward, just barely, just enough to feel the head of Katsuki's cock nudge against his opening. "Give Mommy her present."
Katsuki's cock pressed against Izuku's entrance, slick with pre-cum and the wetness of his mother's cunt. The head nudged, pushed, found the opening—and then stopped. Katsuki's whole body went rigid, his breath catching in a sharp, panicked hitch. "Mommy, I—" His voice cracked, high and small, a child's voice. "I don't know how. I've never—I've never done this before."
Izuku's heart stuttered. His son's virginity. His baby boy was about to give him something no one else had ever had. A wave of possessive heat rolled through him, making his cunt clench around nothing, desperate for the stretch that hadn't come yet. "Oh, baby boy," he breathed, reaching up to cup Katsuki's face, thumb tracing the sharp line of his jaw. "You've never been inside anyone?" Katsuki shook his head, eyes wet, lips trembling. "Then Mommy gets to take your first time. Gets to feel his baby boy's first time buried deep inside his cunt. Do you know how special that makes me feel, Kacchan?"
Katsuki whimpered, his hips twitching forward, the head of his cock slipping half an inch into Izuku's heat before he pulled back, scared. "What if I'm bad? What if I hurt you? What if I—"
"You won't." Izuku's voice was honey and steel. He spread his legs wider, hooked his hands behind his knees, pulled himself open like an offering on an altar. "You can't be bad, baby boy. You're made from this pussy. Your cock was shaped by Mommy's walls. It knows exactly where to go. So stop thinking and *fuck Mommy's cunt however you want.*" His voice dropped, rough and desperate. "Fuck it like crazy. Slam into Mommy's womb. I know there's another baby in there, but that's *your* womb, Kacchan. It's always been yours. Mark it. Put your thick cummies inside Mommy's womb. Paint it white. Claim it."
Something in Katsuki's eyes broke—the last thread of hesitation snapping like a rubber band. His hands found Izuku's hips, gripping hard enough to bruise, and he pulled back, positioned himself, and *slammed* forward in one violent, desperate thrust.
Izuku screamed.
Not a whimper. Not a moan. A full-throated, animal scream as his son's cock buried itself to the hilt inside him, stretching him open in a way he hadn't felt in eighteen years—since the last time he'd pushed a baby out of this same cunt. The thickness, the heat, the way Katsuki's cock filled every inch of him, pressing against his walls, nudging against his cervix, making his whole body seize and shudder. "*Fuck—!*" Izuku's back arched off the bed, his hands flying to Katsuki's shoulders, nails digging into skin. "*Yes—yes, baby boy—fuck Mommy's cunt—*"
Katsuki pulled out and slammed back in, a guttural growl tearing from his throat. "Mommy—*fuck*—Mommy's pussy feels so good—" He was already losing control, his hips moving in a frantic, animal rhythm, no finesse, no technique—just pure, desperate need. "So tight—*so wet*—I can feel Mommy's walls squeezing me—"
"That's it, Kacchan—*that's it*—" Izuku's voice was wrecked, his words coming in gasps between thrusts. "Your fat cock—*fuck*—your fat cock is stretching Mommy so good—filling me up—marking your womb—" He threw his head back, tears streaming down his cheeks, a smile splitting his face. He was being fucked by his son. His baby boy. The child he'd pushed out of this same pussy was *inside* it now, slamming into his depths like a man possessed. "—*more*—give Mommy more—fuck your cum deep into my womb—put another baby in me—fill me up until I'm dripping with you—"
Katsuki's rhythm turned savage. He pulled out until only the head remained inside, then drove forward with his full weight, his balls slapping against Izuku's wet skin, the sound of their bodies colliding filling the room—wet, obscene, perfect. "I'm gonna—Mommy, I'm gonna—" His voice broke, high and desperate, a child on the edge of something too big to contain. "I'm gonna cum inside Mommy's womb—gonna fill it up—gonna make sure Mommy remembers who he belongs to—"
"*Yes, baby boy—yes—*" Izuku's legs locked around Katsuki's waist, pulling him deeper, holding him there, trapping him inside. "Cum inside Mommy. Fill your womb with your thick cummies. *Mark it. Claim it. Make it yours forever.*" He felt Katsuki's cock swell, pulse, and then a hot rush flooded his insides—thick, copious, spraying against his walls, painting his cervix, filling the space where his unborn child grew with his firstborn's seed.
The flood of Katsuki's seed triggered something deep inside Izuku—a pressure that had been building since the moment he'd first seen his son's cock, since the first time he'd tasted him, since he'd felt that desperate mouth latch onto his breast. His whole body seized, back arching off the mattress, and then the wave broke. Not a trickle. Not a normal climax. A gush—hot and violent—that sprayed from his cunt in a thick, pulsing arc, soaking his thighs, the sheets, Katsuki's stomach, the headboard behind them. It kept coming. Wave after wave, his body convulsing, squirting like he'd lost all control of his bladder, except it wasn't piss—it was pure, undiluted pleasure pouring out of him in a torrent that seemed impossible, that shouldn't have been able to come from his small body.
Katsuki's eyes went wide, his mouth falling open as he watched his mother's cunt spray liquid across the bed, drenching everything. "*Holy shit—*" His voice was high, awestruck, reverent. "Mommy, you're—you're *gushing*—" He pulled back slightly, watching his own cock, still buried inside Izuku's spasming hole, get bathed in the flood. The sight made his balls ache, his cock twitch, still rock hard despite having just emptied himself. "*Fuck*, Mommy—"
Izuku couldn't stop. His body kept squeezing, kept releasing, kept squirting in long, wet pulses that painted the sheets in translucent ribbons. His vision went white, his mouth open in a soundless scream, every nerve ending on fire. But even through the blinding intensity, one thought surfaced, desperate and clear: *More. I need more. He can't stop yet.*
"Keep—keep fucking me—" The words came out broken, barely a whisper, but Izuku forced them past his trembling lips. His hands found Katsuki's hips, gripping hard, trying to pull him deeper even as his cunt kept spraying. "Don't stop, baby boy—*please*—fuck Mommy's squirting cunt—fuck it harder—"
Katsuki's brow furrowed, confusion flickering through the haze of lust. "But I already came inside you—"
"*I don't care—*" Izuku's voice cracked, his hips bucking up, grinding against his son's still-hard cock. "You're still hard, Kacchan—I can feel you—you're still hard inside me—so *fuck me*—" He sobbed, tears streaming, body still squirting in diminishing waves. "Fuck past my cervix—fuck into my *womb*—I want to feel you inside the place where I grew you—I want your cock in the same hole you came out of—"
The words hit Katsuki like gasoline on a fire. His eyes darkened, his grip on Izuku's hips tightening until his knuckles went white. He pulled back—not pulling out, just repositioning—and then drove forward with a force that made the bed frame slam against the wall. The angle changed. Something shifted. And Izuku felt the head of his son's cock nudge against something deeper, something that made stars burst behind his eyes.
"*There—*" Izuku gasped, his nails raking down Katsuki's back. "*Right there—fuck past it, baby boy—push into Mommy's womb—*"
Katsuki's teeth bared, a growl ripping from his throat as he slammed forward again, harder, his cockhead pressing against the tight ring of Izuku's cervix. For a moment it resisted, refusing to yield—and then it gave way with a pop that Izuku felt in his throat, in his teeth, in the desperate clench of his cunt. The head pushed through, sliding into a space that was hot and tight and *holy*—the place where his sibling is growing, the sacred hollow that had once held Katsuki himself.
"*Mommy—*" Katsuki's voice broke, high and shattered, as he felt the new pressure, the impossible depth. "I'm—*inside*—I'm inside your *womb*—"
"Yes—*yes*—" Izuku was sobbing openly now, his body trembling, his cunt clenching around the shaft while his cervix gripped the head like a second mouth. "You're home, baby boy—you're *home*—this is where you belong—right here inside Mommy's body—" He wrapped his legs around Katsuki's waist, locking him in, trapping him at that impossible depth. "Now *move*. Fuck your womb. Fuck the place you were born from. *Claim it.*"
Katsuki's hips drew back, the head of his cock dragging through the tight ring of Izuku's cervix with a wet, popping sound that made them both gasp. For a moment, only the shaft remained inside his cunt, his womb suddenly empty, aching. Then Katsuki slammed forward again—harder, faster, his entire body throwing itself into the thrust. The head punched through the cervix a second time, burying itself in the hot, clutching space where his sibling floated, and Izuku's back arched off the bed, a scream tearing from his throat as another gush of clear liquid sprayed from his cunt, drenching Katsuki's thighs.
"*Fuck*—" Katsuki's voice was ragged, animal, his teeth bared as he pulled out again, leaving only the tip, then drove back in, popping through the cervix once more. Each entry made a sound—a wet, thick pop—and each exit left Izuku's womb clenching around nothing, desperate to be filled. "Mommy's womb—*mine*—it's *mine*—" He punctuated each word with a brutal thrust, his balls slapping against Izuku's soaked perineum, the bed frame slamming against the wall in a steady, frantic rhythm. "That baby in there—he doesn't get it—*I* get it—I was first—"
Izuku's hands scrabbled at the sheets, his vision white, his mouth open in a soundless, continuous scream. Every time Katsuki's cock punched into his womb, his cunt convulsed and another wave of squirt erupted, soaking the mattress, running down his thighs in hot rivulets. "Yes—*yes*—claim it, baby boy—*fuck*—it's your womb—it's always been your womb—" His words came in broken gasps, his body beyond his control, a fountain of pure pleasure pouring out of him with every thrust. "That baby—he's just visiting—you're the *king*—you're my firstborn—my *first*—"
Katsuki's rhythm turned savage, no finesse, no restraint—just a teenage boy fucking his mother's womb with desperate, jealous fury. He pulled out until the head caught on the cervix, then drove forward with his full weight, popping through, grinding deep, holding there for a second before pulling back to do it again. "I'm gonna fill it up—gonna fill Mommy's womb with so much cum that baby won't even know where he is—" His voice cracked, high and childish, a sob mixing with the growl. "Mommy's womb is *my* room—he's sleeping in *my* room—"
Izuku's legs tightened around Katsuki's waist, pulling him deeper, trapping him on the inward stroke. "Then fill it, baby boy—*fill it*—paint your womb white—mark it so he knows—so everyone knows—" He was crying openly now, tears and sweat and squirt mixing on the soaked sheets, his pregnant belly bouncing with each impact, the baby inside shifting, reacting to the violent rhythm. "Cum inside Mommy again—*please*—I need to feel your hot cum inside your womb—I need to feel you claiming what's yours—"
Katsuki's hips stuttered, his rhythm breaking as the pressure built, his balls drawing up tight against his body. "I'm gonna—Mommy, I'm gonna cum again—" He slammed in one last time, burying himself to the hilt, his cock pulsing as a second hot flood erupted inside Izuku's womb—thick, copious, spraying against the walls where his sibling grew, mixing with the first load, filling the space until it overflowed, trickling back out around the shaft in white streaks. "*Mommy*—" His voice was a child's cry, broken and reverent, as he emptied himself completely.
The second flood triggered another climax in Izuku—deeper than the first, if such a thing was possible. His whole body seized, back arching, and a torrent of squirt exploded from his cunt, soaking Katsuki's chest, his stomach, the headboard, the wall behind the bed. It kept coming, wave after wave, his body wringing itself dry, his voice lost in a silent scream that went on and on. When it finally subsided, he lay gasping, trembling, his cunt still clenching around his son's cock, his womb full and heavy with Katsuki's seed.
Katsuki didn't pull out. He stayed buried deep, his forehead pressed against Izuku's collarbone, his breath hot and ragged against the sweat-slick skin. "I'm not done," he whispered, his voice small but fierce. "I'm gonna fuck you all day, Mommy. All day. Until you can't walk. Until you can't remember a time when you weren't full of my cum."
Izuku's hand found the back of his son's head, fingers tangling in the spiky blond hair, pulling him closer. "Good," he breathed, his voice wrecked, raw, but certain. "That's exactly what Mommy wants for Mother's Day. To be your hole. Your womb. Your home." He shifted his hips, feeling Katsuki's cock still hard inside him, already twitching with the need for another round. "Now fuck me again, baby boy. Pop into your womb and cum again. Mommy's not satisfied yet."
The morning light shifted through the curtains, turning from pale gold to harsh white as the hours bled together. Izuku had lost count of how many times Katsuki had filled him—his womb sloshing with each thrust, cum leaking down his thighs in thick white rivulets that stained the already-soaked sheets. The mattress was ruined, the headboard smeared with translucent ribbons of squirt that had dried to sticky patches, and still Izuku's body found more to give. Every time Katsuki's cock punched through his cervix, another wave erupted from his cunt, spraying across the bed in a desperate offering. "Mommy's squirt fountain," Katsuki had called it, somewhere around the fifth hour, his voice reverent and cruel, and Izuku had come undone at the words, gushing across his son's chest.
By midday, the bed was uninhabitable. Katsuki had pulled them both to the floor, laying Izuku on his back on a pile of towels he'd grabbed from the hall closet, his pregnant belly gleaming with sweat and cum and squirt. He fucked Izuku there too—doggy style, with Izuku's belly pillowed on a folded blanket, his knees raw against the hardwood. Then on his side, one leg thrown over Katsuki's shoulder, their bodies slotting together like they'd been made for this exact purpose. "Kacchan—" Izuku's voice was gone, wrecked to a hoarse whisper, but he kept begging, kept pulling his son deeper, kept telling him to cum inside his womb again. "Fill your room, baby boy—fill it up until your brother knows who owns it—"
Katsuki's eyes went wild at those words, his hips slamming forward with renewed fury, and Izuku felt the eighth—maybe ninth—load spray deep inside him, hot and thick, mixing with all the others. The baby inside him kicked, reacting to the pressure, and Izuku's hand flew to his belly, tears streaming down his face as another orgasm ripped through him, his cunt clenching around his son's cock while his body emptied itself in a long, pulsing gush that soaked the towels beneath them. "He knows, Mommy," Katsuki whispered, his forehead pressed against Izuku's, breath hot and ragged. "He knows I'm the king. He's just a visitor."
The afternoon sun blazed through the windows as they migrated to the living room. Izuku bent over the arm of the leather sofa, his belly hanging beneath him, his tits swinging with each brutal thrust. Katsuki had fucked him on every surface in the house by now—the kitchen counter, the dining table, the bathroom floor with the shower still running, leaving Izuku pressed against the cold tile while hot water sluiced over his back. "You're gonna destroy me, baby boy," Izuku gasped, and Katsuki's laugh was broken and beautiful, a child's laugh tangled with a man's hunger.
"That's the point, Mommy. I'm gonna fuck you until you can't remember what it felt like to be empty." And he did. He kept going, kept cumming, kept filling Izuku's womb with load after load until Izuku's belly felt heavier, fuller, as if the sheer volume of seed was pushing against the baby from the outside. Izuku loved it. He loved the slosh when he moved, the constant wet trickle down his thighs, the way his son's cum dripped from his cunt like a never-ending offering.
Dusk crept in, painting the walls in shades of amber and rose, and they ended up back in the bedroom—the only room that still smelled like them, like sex and sweat and their mingled fluids. Katsuki had Izuku on his back, legs folded to his chest, watching his own cock disappear into his mother's swollen, dripping hole. Every time he pulled out, cum leaked in thick white ropes, coating his shaft, his balls, the sheets beneath them. And still Izuku's body kept producing squirt—smaller bursts now, but constant, a steady stream of clear liquid that wept from his cunt with every thrust.
"How do you still have more?" Katsuki's voice was awed, his movements slowing as exhaustion crept in, his body trembling with the effort of another climax. "Mommy, you've been squirting all day—"
"Because I'm your mommy," Izuku breathed, his hand finding Katsuki's cheek, thumb brushing away a stray tear. "And Mommy's body will never run out for his baby boy. I'll keep giving until I'm empty. And then I'll find more." His hips rolled up, grinding against his son's cock, drawing him deeper. "Now cum inside me again, Kacchan. Fill your womb one more time. Make sure your brother knows he's swimming in your cum."
Katsuki's face contorted, pleasure and something darker twisting together, and he slammed forward with the last of his strength, burying himself to the hilt. His cock pulsed, throbbed, and another wave of hot cum flooded Izuku's depths—thinner now, the product of a dozen previous climaxes, but still thick enough to coat Izuku's walls, to trickle out around the shaft in milky streaks. But even as his body emptied, even as he collapsed onto Izuku's chest, a tiny voice in the back of his mind whispered something darker, something he didn't dare speak aloud. *I wish he'd drown in it. I wish my baby brother would choke on my cum and die inside Mommy's womb so I could be the only one again.*
Izuku felt his son's body go slack, heard his breathing slow into the rhythm of near-sleep, and he wrapped his arms around him, holding him close. His womb was so full it ached, a deep, heavy pressure that made his entire abdomen throb with each heartbeat. Somewhere in that flooded space, his unborn child floated, safely protected in his anabiotic sack. Izuku pressed a kiss to Katsuki's forehead, his voice a feather-light whisper against the sweat-damp skin. "You're my first. My only. That baby in there? He's just borrowing your room, baby boy. It will always, always be yours." And in the gathering dark of Mother's Day, they lay tangled together, the line between them erased, two bodies that had become one in every way that mattered.