The salt air on the balcony was supposed to feel free. Katsuki gripped the railing, the champagne flute cold in his other hand. Below, the endless blue of the ocean stretched, a vacuum.

"Isn't it wonderful, Kats?" Inko sighed beside him, her silk robe fluttering. "A full week. Just us."

He didn't correct her. He drank the champagne. It tasted like metal.

"Mom! Kacchan!" The voice was a sugar-coated dart. Izuku slid the balcony door open, a vision in a scandalously small red bikini that clung to every curve of his lean, freckled frame. He held a tube of sunscreen. "The deck is getting crowded. You should claim chairs before it's a warzone."

Inko beamed. "What a thoughtful boy. Katsuki, darling, could you help him with his back? I want to finish my coffee." She patted his arm and drifted inside.

The door clicked shut. The silence was louder than the engine hum.

Izuku didn't wait. He turned, presenting his bare back, the dip of his spine leading down to the tied strings of his bikini bottom. "You heard her, Daddy."

Katsuki's jaw ached. He set the flute down with a sharp click. He took the sunscreen, squeezed a dollop onto his palm. The cream was cold. Izuku's skin was warm. He spread it over the sharp wings of Izuku's shoulder blades, his touch clinical, rough.

"You shouldn't be here," Katsuki said, his voice low.

"Where else would I be? You're my family now." Izuku arched into the touch, a soft sigh escaping him. "Lower, please. I burn so easy."

Katsuki's hand slid down. The muscles of Izuku's back shifted under his fingers. He could feel the heat radiating off him, the faint scent of coconut and something inherently Izuku—a musk that went straight to his gut. His cock, traitorous and heavy, began to thicken against his linen pants.

"There you two are!" Denki's cheerful call made Katsuki snatch his hand back. Denki bounded onto the balcony, followed by a stiff-looking Eijiro. Denki wore a matching yellow bikini, his lean body gleaming. "We got the chairs. Prime real estate by the pool."

Eijiro wouldn't meet Katsuki's eyes. He looked carved from stone, his professional polo at odds with the vacation setting. "Inko inside?" he asked, his voice strained.

"Yeah," Katsuki grunted.

Inko waved a dismissive hand, her smile warm but tired. "You all go enjoy the sun. I think I'll stay in and finish my book. The quiet will be lovely." She pressed a kiss to Katsuki's cheek, her jasmine scent a fleeting ghost, and disappeared into the cool dimness of the stateroom.

The pool deck was a riot of reflected light and turquoise water. Denki had secured four loungers in a row. He was already on his stomach, the ties of his yellow bikini bottom loose, as Eijiro, stiff in his polo and shorts, applied sunscreen to his back with a clumsy, red-faced intensity.

"Lower, Ei," Denki purred, his face turned toward Izuku's chair. "You missed a spot."

Izuku occupied the lounger beside Katsuki's. He had untied the top of his red bikini, the fabric laid aside. He lay on his back, eyes closed behind dark sunglasses, his small, perfect tits exposed to the sun. The freckles dusted across his chest and over the puffy, pink nipples. They peaked in the warm air.

Katsuki sat rigidly on the edge of his own chair. He stared at the ocean, the horizon line, anything else. His gaze kept snapping back, magnetized, to the rise and fall of Izuku's chest.

"See something you like, Kacchan?" Izuku murmured, not opening his eyes. A faint, knowing smile touched his lips.

"Put your top on," Katsuki said, his voice a graveled scrape.

"Why? It's a honeymoon. Everyone's a little bare." Izuku shifted, arching his back slightly. The movement made his nipples tighten further. "You should relax, Daddy. You're so tense."

Beside them, Eijiro's attempts at a clinical massage had devolved. Denki had guided his hand lower, under the waistband of his bikini bottom. Eijiro's ears were crimson. "Denki, we're in public," he hissed, but his hand didn't withdraw.

"So?" Denki giggled, the sound bright and lewd. "No one's looking at us. They're all looking at the main event." He tilted his head meaningfully toward Katsuki and Izuku.

Izuku reached out a hand, not looking, and let his fingers brush Katsuki's clenched fist where it rested on the plastic weave of the lounger. "He's right. Everyone can feel it. This... ache between us." His finger traced a vein on Katsuki's wrist. "Your heart is pounding. I can see it in your throat."

Katsuki’s throat worked, a hard swallow he couldn’t stop. His gaze was locked on the junction of Izuku’s thighs, where the red bikini bottom was pulled taut over his pussy. A dark, wet spot was blooming in the fabric, precise and undeniable. Izuku’s hand drifted down his own stomach, fingers tracing the damp patch, his breathing deliberately slow and deep.

Beside them, Denki pushed back against Eijiro, grinding his cute, round ass against the hard line of the older man’s cock straining against his shorts. “Mmm, someone’s excited,” Denki sing-songed, looking over his shoulder. “You gonna do something about that, Ei? Or just let it ache?”

Eijiro’s jaw was clenched, his professional composure fissuring. “Denki. Stop.”

“You stop,” Denki giggled, arching his back. “Your hands are still on me.”

Izuku’s voice was a low, private thrum meant only for Katsuki. “See how easy it is? To just… want.” He hooked a finger under the side string of his bikini bottom, pulling it aside for a fraction of a second. A glimpse of slick, bare skin. The wet spot grew. “It’s so hot out. I’m getting all… sticky.”

“Stop it,” Katsuki growled, but his voice lacked force. It was a plea.

“Make me.” Izuku turned his head on the lounger, sunglasses sliding down his nose. His green eyes were bright, predatory. “You’re the adult. You’re my stepfather. Tell me to behave.” He shifted his hips, a slow, deliberate roll that made the wet fabric shine. “Or put your hand right here and feel how little I listen.”

Katsuki’s breath sawed in his chest. The pool water glittered, children shrieked, and all of it was white noise. The only real things were the salt air, the sun beating on his neck, and the obscene proof of Izuku’s arousal two feet away. Katsuki can’t help but swallow hard while he watches Izuku play with the wet spot form on his bikini bottoms pulled tight over that pussy. Denki can feel Eijiro’s hard cock throb against his ass, he rubs his cute butt against it. His hands, which had been frozen on Denki’s hips, dug in, yanking the younger man back against him fully. He buried his face in Denki’s neck, a shudder running through his bulky frame. “Just… be quiet for a second.”

Denki’s smirk was victorious. “Quiet isn’t really my thing, big guy.” But he stilled, letting Eijiro hold him, both of them turned toward the other pair as if watching a more compelling show.

Izuku reached out, his fingers wrapping around Katsuki’s wrist. His touch was searing. “It’s okay,” he whispered, guiding Katsuki’s hand from the plastic weave of the chair toward his own lap. “She’s not here. It’s just us. Just you and your son.”

Katsuki’s arm didn’t resist. It was leaden, paralyzed by want. His fingers trembled as the back of his knuckles brushed the heated, damp fabric. A jolt went through him, his cock throbbing viciously against his zipper.

“Feel it,” Izuku breathed, pressing Katsuki’s hand down fully. The heat was stunning. Through the thin material, Katsuki could feel the swollen shape of Izuku’s pussy, the distinct, slippery wetness. “That’s all for you, Daddy. It’s been like this since you touched my back.”

Katsuki’s eyes screwed shut. He was gone. The last brittle wall crumbled. His fingers curled, pressing into the soaked fabric, and Izuku gasped, a sharp, sweet sound lost in the poolside din.

Eijiro’s control snapped. He shoved the waistband of his shorts down, his thick, flushed cock springing free. He didn’t hesitate, yanking the side of Denki’s yellow bikini bottom aside and pressing the head against his slick entrance. “You win,” he growled into Denki’s neck, and pushed slowly, inexorably, inside.

Denki gasped, a sharp, high sound, his back arching as he was filled. “Fuck, Ei… finally.”

Katsuki watched, hypnotized, as Izuku’s fingers closed over his own on the wet fabric. “My turn,” Izuku breathed, and guided Katsuki’s hand to hook under the string at his hip. With a sharp tug, the red fabric was pulled aside, baring him completely to the sun and Katsuki’s gaze. His pussy was glistening, swollen, a mess of slick arousal. Katsuki’s thumb, acting on a primal instinct, found his clit and began to circle, fast and rough.

Izuku cried out, his hips bucking off the lounger. “Yes! Just like that, Daddy.”

“Someone will see,” Katsuki muttered, but his fingers kept working, spreading the wetness, his other hand gripping Izuku’s thigh to hold him still.

“Let them see,” Izuku panted, his head thrown back. His sunglasses fell to the deck. “Let them see how you touch your son.” Beside them, Eijiro was moving in Denki with deep, measured strokes, Denki’s giggles turned into choked moans.

Katsuki leaned closer, his voice a raw scrape against Izuku’s ear. “You’re dripping. Making a mess of the chair.”

“You’re making me,” Izuku accused, his green eyes blazing up at him. He reached down, his fingers wrapping around Katsuki’s wrist, forcing his touch deeper. “Feel it. That’s all you. You did this.”

Katsuki could feel the hot, silken clutch of him, the irresistible pull. His own cock was a painful, throbbing weight. “Fuck.”

“Yeah,” Izuku agreed, a wild smile on his face. “Fuck. Do it. Right here. Claim me in front of everyone.”

Eijiro’s pace was increasing, the sound of skin on skin joining the poolside noise. Denki was babbling. “Right there, yes, harder, you’re so big—”

Katsuki’s free hand went to his own waistband, fumbling with the button of his linen pants. The zipper gave way. He freed himself, his thick, uncut cock jutting out, flushed and leaking. Izuku’s eyes devoured the sight. “Oh, God,” he whispered.

“You want this?” Katsuki asked, his professional composure ashes, his voice pure gravel.

"Come here," Katsuki growled, his voice stripped bare. He lay back against the slatted plastic, his huge, flushed cock standing thick and obscene against his stomach. "Fuck yourself on it."

Izuku’s breath hitched. He moved with a fluid, eager grace, swinging one leg over Katsuki’s hips, his slick pussy hovering just above the swollen head. His green eyes were wide, fixed on Katsuki’s face. "Say it again."

"Fuck your slut pussy on my cock," Katsuki commanded, his hands finding Izuku’s sharp hips, fingers digging into bone. "Now."

Beside them, Eijiro had one brawny arm locked around Denki’s waist, holding him up as he pistoned into him from behind. The slap of skin was wet, rhythmic. Denki’s head lolled back on Eijiro’s shoulder. "Yeah, fuck, just like that," he chanted, "you’re so deep—"

Izuku lowered himself, not taking his eyes off Katsuki. The first press was an electric, silken shock. The head of Katsuki’s cock parted him, stretching the swollen, eager opening. Izuku’s mouth fell open in a silent gasp.

"Feel that?" Katsuki rasped, his hips lifting minutely to meet him. "That’s all you. You made this."

"I know," Izuku breathed, and sank down the rest of the way in one slow, devastating slide.

The fullness punched the air from Izuku’s lungs. He braced his hands on Katsuki’s chest, fingers splaying over hard pectorals. Katsuki’s cock was buried to the hilt inside him, a brutal, perfect fit. The heat was stupefying.

"Oh, God," Izuku whimpered, his body trembling with the stretch. "Daddy…"

Katsuki’s head fell back against the lounger, his glasses askew. His knuckles were white where he gripped Izuku’s hips. "Move."

Izuku began to ride him, a slow, grinding roll of his hips. Each rise and fall was a wet, filthy sound, lost in the poolside cacophony. His slickness coated them both, dripping down onto Katsuki’s balls and the fabric beneath.

Eijiro’s thrusts grew more frantic, his teeth gritted. "Gonna cum," he warned Denki, his voice a ragged growl.

"Do it," Denki moaned, pushing back against him. "Fill me up, Ei. Right here."

Katsuki watched, mesmerized, as Izuku’s body took him. Sweat beaded on the younger man’s freckled chest, his small nipples tight and pink. "Faster," Katsuki ordered, giving a sharp upward thrust that made Izuku cry out.

"You’re so big," Izuku panted, obeying, his pace quickening. The lounger creaked under them. "It’s—ah!—it’s so good."

"Whose is it?" Katsuki demanded, his hands sliding around to grip Izuku’s ass, pulling him down harder onto each thrust.

"Yours," Izuku gasped, his green eyes glazing. "Yours, Daddy, only yours."

Denki’s body went taut, a high, keening sound escaping him as he came, squirting onto the deck with a shuddering splash. Eijiro followed with a choked roar, his hips stuttering as he emptied himself inside him.

The sight, the sounds, pushed Katsuki to the edge. His control shattered. He bucked up into Izuku with a final, brutal surge, his orgasm tearing through him like a lightning strike. He came with a raw, guttural sound, pulsing deep inside his stepson.

Izuku felt it, the hot flood triggering his own release. He arched, screaming Katsuki’s name as he squirted, the fluid soaking Katsuki’s stomach and the chair between them in a warm, copious rush.

For a long moment, there was only the sound of their ragged breathing and the distant shrieks of children in the pool. Izuku collapsed forward, his sweat-slick chest heaving against Katsuki’s. Katsuki’s softening cock was still inside him, a claiming that felt more permanent than any ring.

Denki giggled, breathless and spent, slumped against Eijiro’s chest. "Wow. Talk about a poolside show."

Eijiro didn’t answer. He was staring at the two entangled men, his face a mask of dazed horror and understanding.

Izuku nuzzled into Katsuki’s neck, his voice a sated murmur. "She’s probably still napping. Our little secret."

Katsuki didn’t respond. He stared at the perfect blue sky, the ship’s horn blaring in the distance, and felt the last of his old life dissolve into the salt air.