"K-Kacchan… I think I'm starting to hear it. The music of the Sea."

"That so?" Katsuki replies, smirking.

Izuku nods. "Y-yeah."

"Tch. Took you long enough."

Izuku laughs softly, the sound blending with the distant hum of the ocean. "It's… beautiful," he murmurs, "Like a song woven into the currents."

Izuku grins. "Do you hear it too, Kacchan?"

Katsuki huffs, flicking a fin against Izuku's side. "Of course I do, dumbass. The ocean's been singing to me since the day I was born."

"But why am I only hearing it now?" Izuku mumbles.

Katsuki's voice drops just a little, quieter now.

"Maybe it's because you're finally ready to listen."

Katsuki sighs.

"Who needs a prince when you've got love of the ocean, Izuku?"

Izuku blinks, startled. "What…?"

"The sea's always been here for you, Izuku," Katsuki continues, "It sings to you, holds you, keeps you alive. And you wanna throw that away for some human who might not even love you back?"

"I never wanted to throw it all away. I…"

"Yes, you did. Why else would you trade away your precious lyre?"

Izuku shuts his eyes.

"You're a mermaid, Deku. You always have been and you always will be one."

"Oh yeah? Then why do I hate being one?!" Izuku exclaims with grief.

"Because you never learned how to love yourself, Deku."

Izuku clenches his fists, his nails digging into his palms. "You don't understand, Kacchan. Humans get to have eternal souls. Mermaids don't. We just… disappear when we die." His voice cracks. "I don't want to be forgotten."

Katsuki scoffs, shaking his head. "You think that the ocean forgets?" He gestures around them, to the vast, endless blue. "Every wave, every current, every song—it remembers all of it. Just 'cause we don't have eternal souls doesn't mean we end up forgotten."

Katsuki crosses his arms. "You act like the sea's some prison, like it's keeping you from what you want. But have you ever stopped to listen to it? To feel it?" He gestures around them, to the shimmering blue stretching infinitely in every direction. "The ocean sings for you, Deku. It carries you, holds you up even when you think you're sinking."

Izuku swallows hard, his tail curling slightly beneath him.

Katsuki's voice softens—just a little. "You say you wanna walk, that you wanna dance under the sun. Fine. Maybe you do. But don't pretend like the sea hasn't given you anything. You were born in its embrace. It's a part of you, whether you like it or not."

Izuku looks down, his hands trembling. The water swirls around him, gentle, familiar.

"The ocean loves you, Izuku. Maybe it's time you started loving it back."

"I… I do love it, Kacchan." Izuku says. "I… I can't deny its beauty."

"But?" Katsuki urges.

"My heart yearns for more." Izuku says.

"Oh?" Katsuki glares, crossing his arms. "Now you're just being greedy."

Izuku flinches at Katsuki's words.

"I'm… I'm not greedy." Izuku mumbles. "I just… I want something different. Something beyond this."

Katsuki scoffs, his tail flicking impatiently. "Please. You've got the whole damn ocean at your fingertips, and now you're whining that it's not enough." His glare sharpens. "That's greed."

"I hear your music, Kacchan." Izuku murmurs. "I hear it loud and clear."

"So then why… why do you fight, Izuku?" Pain flashes through Katsuki's eyes.

Izuku smiles sadly. "Because I'm crazy. You know that, Kacchan."

"Yeah, you are." Katsuki's fists clench. "You are, Deku. Whatever. Do what whatever you want. Go chase your dreams. It doesn't matter. I'll keep doing everything in my power to make you see why being a mermaid is amazing. And you'll eventually come around, I know it."

As Katsuki swims away, Izuku sighs.

"You already have made me see the benefits of being a mermaid." Izuku replies. "Kacchan."

"Which is why, even though I'm part human now… I hope I never fully lose my mermaid part, too."

Izuku curls into himself.

"Is… is that too much to ask for, ocean? Can you hear me, ocean? Can you hear me?"

It's faint, but…

Izuku can hear a melody whispering itself into his ears.