The water that Sanji is breathing feels stale and thin, it's giving him a splitting headache. Not to mention that whatever he's leaning on is giving him back cramp like crazy and smushing his dorsal fin at an awkward angle. Sanji surfaces blearily and finds himself in a smallish wood panelled bathroom. What he'd subconsciously mistaken for seaweed is in fact the top of Zoro's head leant against the edge of the bath.

Zoro is snoring in a loud fashion and Sanji is frankly stunned that he's managed to sleep through it. Sanji leans to the side, stretching out his spine and inadvertently getting a better look at the sleeping man. Behind his eyes visions of Zoro changing the night before flick over and over like a mental slideshow. Sanji's ear fins twitch with pent up energy and Sanji squirms uncomfortably in the bath.

He's close enough to Zoro to feel the warmth running from his skin. Sanji runs so much colder than him that the difference is stark without even touching him. He knows just how hot Zoro is, he's had his arms around him many times before when trying to drown him. Now though with Zoro sleeping blissfully unaware next to him Sanji finds his fingers frozen just mere inches from Zoro's cheekbone. The heat from him ripples over and Sanji is so busy quashing the urge to just touch him that he can't bring himself to take his hand back.

Long dark green eyelashes fan out against tan skin and without the scowling tension of being awake Zoro is kind of... handsome in his own way. Sanji feels his ear fins flushing red and suddenly he might as well be fourteen again and crushing on the pretty mermaid girls in the pools. It's different this time though, Zoro is a human and it'd never work. He's spent months trying to murder him for one. Why's he even thinking about this anyhow? He must be sleep deprived. Anyway, even if he wasn't nothing like that ever works for Sanji because of who he is.

Shit, he needs to get out of here. Zoro dragged him back here to sleep as payment for saving his stupid human life and now he's got a little sleep he can get away and things can go back to normal, when Sanji was just angry at him for being an ungrateful fucking human and he didn't have this strange feeling in his chest.

Sanji rests his hands on the rim of the bath and hauls himself upwards until he's out of the water to his waist. If his hair covered his ear fins then maybe someone could have looked at him right now and assumed that he was normal. Hah, he's far from that. Zoro is still sound asleep and Sanji intends to keep it that way, all he needs to do is stretch across and grab that towel rail, then he can haul himself slowly out of the water and out of the room, clean out of the ship and back into the sea. He won't have to have any awkward conversations with Zoro or even look at him at all. Sanji glances down at him and remembers the smooth ripple of Zoro's abdominals as he took off his soaked shirt on the beach last night. He remembers the way Zoro's skin shone in the moonlight and how the cold made his nipples- oh for fuck's sake! Sanji shakes his head hard and hefts himself forward. His fingers just snag the towel rail and he manages to get a grip on it. He adjusts the hand still on the rim of the bathtub and then shifts his weight to the towel rail.

The towel rail breaks from the wall with a loud bang, sending Sanji fin over ass onto the floor and because the universe hates him, flipped onto his back in Zoro's lap.

Even Zoro isn't a deep enough sleeper to sleep through that.

"Uh. Hi?" Sanji chokes out, mortification colouring his skin.

"Morning to you too." Zoro responds, yawning wide enough to crack his jaw and shifting his legs under Sanji's back slightly.

"'f you wanted to get out you coulda woken me." Zoro grumbles, rubbing his eyes sleepily.

"I didn't want to." Sanji replies petulantly as he scrambles out of Zoro's lap in embarrassment.

"Aw, sweet. I wouldn't have minded." Zoro says with an air of teasing and a smirk on his lips.

"Well maybe I wasn't thinking about you. Maybe I find every conversation with you so painful and stupid that it lowers my IQ and I didn't want that to happen any more." Sanji bites back, curling his tail under him so that he can sit up to a proper height and glare at Zoro.

"I didn't know IQ could go into negative numbers." Zoro retorts with a full grin.

"It's rude to talk about yourself so much seaweed brain." Sanji snaps back. He expects Zoro to argue back, to bait him and to snarl but instead Zoro just laughs. It's brilliant and bright and that tight swirling feeling is back in Sanji's chest again. He finds himself watching Zoro's mouth as he laughs, watches how his lips move and-

Sanji turns his head away sharply and moves towards the bathroom door. He pulls himself up onto his tail and wrenches the door open. Before he can drag himself through though there is a pair of warm arms around him, one under his tail and the other under his arms.

"HEY! PUT ME DOWN! I DON'T NEED YOUR HELP!" Sanji rails furiously.

"Never said you did, but it'd be a dick move to make you drag yourself out when I can help just as easily." Zoro responds

Sanji has a million things to say to this, he's sure he does. Only... only Zoro's holding him in such a way that his breath is rippling the thin membrane of Sanji's ear fin. Zoro's talking now about something stupid, something about the ship and where they're going and just... Sanji tilts his head ever so slightly and now when Zoro enunciates especially clearly his lips just brush against Sanji's fin. The breath catches in Sanji's throat and his spine goes stiff.

Zoro places him softly on the deck and Sanji instantly misses the accidental brush of Zoro's lips on him. Of course he immediately berates himself for it but it doesn't remove the feeling at all.

"Hey, are you ok? You've barely said anything and that's not like you." Zoro frowns leaning over him and kneeling on either side of Sanji's tail.

"I..." Is about all Sanji can manage.

Zoro frowns and squints at him, leaning forward more so that he can look closely at Sanji, his hips shifting closer to Sanji's tail.

"You didn't fracture your ribs again yesterday did you?" Zoro questions, his eyes dropping to Sanji's side. One too warm hand comes up and touches along Sanji's ribs. Nerve endings flash and flare signals inside Sanji's head and he hisses on instinct. In the opposite of what Sanji wants him to do Zoro snatches his hand back.

"Shit, sorry. I'll get Chopper if it hurts. You said you were fine, did he miss anywhere?" Zoro asks and runs a hand along the muscles of Sanji's tail. The merman lets out a startled yip and Zoro's hand, thick and hot, stops where it is. Zoro is looking down at Sanji's tail.

"You know, since I've met you I've wondered something." Zoro says, seemingly out of the blue. Sanji's tongue isn't responding inside his mouth and it only gets worse as Zoro moves his thumb, dark eyes watching Sanji carefully as the blush spreads from his ear fins all the way across his cheeks.

"You're not exactly human down here, and I know how fish fuck but how do mer people like you fuck? Or... have I got my hand on some kind of hidden dick of yours here? Or perhaps I was right when I first met you, perhaps you've not got a dick at all, maybe you've got something else going on down here." Zoro says, his voice deep and gravelled as he rubs a thumb along the scales of Sanji's tail.

His hands are distracting but his words are enough to get Sanji's brain into gear. Rage snaps through him quick as lightning and his tail snaps itself taut around Zoro's midsection and flings him into a wall. He hauls himself up onto the railing of the ship and glares ice at Zoro.

"This whole thing was just a blip. Next time I see you marimo you'll be drowning under the sea at my hands. Mark my words I'll kill you." Sanji snarls and hurls himself into the sea.

The cold washes over Sanji as he dives. Sanji tries to focus on that rather than the itch under his skin from all of the places where Zoro touched him. He forces himself to remember Zoro's words, his last little taunt and suddenly the idea of dragging Zoro down deep and dark into the sea and watching his lungs crush in on themselves is incredibly satisfying.