Pirate eijirou kirishima x mermaid/human reader twin cousin of mina ashido

Pirate Au

Genre: smut

(🔞⚠️ ship sex , pet name 🔞⚠️)

story idea: you are y/n ashido. half mermaid and half human. you are also part of the crew of the famous pirate captain eijiro kirishima. your crush unfortunately he never saw anything in even when he saw you in mermaid form. that didn't stop him from flirting with your twin cousin mina and the rest of the female crew mates on board his ship.  2 years had past before you came back to the ship. eijiro found out that you had a crush on him and decided to set things right. 

-------------------------------------------------------------------------------------------------------------------------------you have always loved the sea. salty sea air. the ocean waves. everything about being on the open ocean. on a ship. you enjoyed. that wasn't the only reason you signed up as crew mate and a life on the open seas. in fact you are half mermaid and half human. the seas is like freedom to you. you got to enjoy the sea both as a mermaid and a human.  

when you saw a stamp on the side of the building ''asking for more female crew mates'' you and your twin cousin signed up for it immediately. that's how you met eijiro kirishima the famous pirate captain. the captain you fell in love. 

when you started off as a deck cleaner. he just ignored you. he was interested in your twin cous mina. so he taught her how to fight. and trained with her until she found herself a bf. her bf in question is hanta sero. you were still cleaning decks and what not. 

the stress of working on the deck wasn't that bad. i mean it wasn't really that bad. you could stare at the ocean and count the fish that come up to see you. it was fun. but it did get annoying after a while. so on your break. you decided to go for a dip in the sea. as you jumped into the sea. 

your fellow crew mates wanted to stop you. ''no leave her, she is half mermaid, she can swing, she'll be fine'' mina said to them ''wait half mermaid and half human thats weird, shouldn't the captain know about this?'' izuku asked ''no he shouldn't, it's nothing of his business, i know where is going anything, if anything happens i'll find her'' mina said to him. 

a month went by and you hadn't come back so your twin cous mina went to find you. she dove into the sea. and started to look for you. she remember the old rock formation for when you and her young. you used to go there when you were stressed or upset. she checked there. she was right. 

she swam over to you ''y/n what are you doing here?, why don't you come back? the crew is very worried about you and the captain is going to get suspicious'' she said to you ''no he has nothing to be sus about mina, he likes you remember and i'm just there scrubbing decks all day along while you and the rest get breaks, i get none'' you said to her 

she was shocked that you never got breaks while working for captain eijiro. ''is that why you look fed up and bored everytime he asks you to do something for him?'' she asked you ''yeah it cause i don't like the job i've been given, it's not fair, i hate it, i know i shouldn't complain but still i don't like it'' you said to her 

mina signed as left you at the rocks. she swam back to the ship. to see the crew and the captain looking at her ''so where is she?'' denki asked ''where is who?, i don't see anyone that is missing from the crew?'' eijiro asked ''your an idiot captain'' katsuki said to him ''i'm  confused'' he said to him ''shut up'' katsuki yelled ''you were saying mina?'' sero asked ''she is fine, is she just tired and fed that's all'' mina said him 

when the captain left the deck to go back to his quarters ''ok now that he is gone, y/n is upset with eijiro, i just couldn't tell that infront of him'' mina said to them ''oh so is upset cause he keeps on ignoring her?'' sui asked ''yeah basically, she is also tired of the deck cleaning she hates it'' mina said to her ''oh so, the captain doesn't know?'' jiro asked ''yeah he doesn't and she doesn't him to know and i would like to keep it that way'' mina said to her.

2 months later. you came back to the ship. your twin cousin mina saw you. the crew were happy to see you back. the captain was well not exactly pleased to you back after being away for to 2 months straight. but it was eijiro's fault for that.  you went on cleaning the deck. and it's not like he asked you to. you just did it of your own accord. 

even tho mina had a bf now. eijiro didn't stop training her to fight ''captain, why don't you train someone else for a while?'' his second in command asked ''who would i train other mina who i want to train'' he said to him ''hmm jeee i don't know captain maybe her fucking twin cousin y/n ashido'' he said to him 

eijiro looked at y/n cleaning the decks ''i don't know, does she know to fight?'' he asked ''yeah she does, her father trained her and me when we were younger, oh right you wouldn't know, that cause you don't care'' she said to him ''y/n stop cleaning, it's time for a break'' she called to you ''ehh no thanks mina, i'm good'' you said to her ignoring eijiro's gaze

''why is not breaking for lunch?'' he asked her ''cause you decided not to give her break'' she said to him ''y/n come on'' she said to you ''fine fine alright i'm coming'' you said to her as you ran past the captain. ''wait sero hold back for just second'' he said to him ''what is it captain?'' he asked ''is y/n ok?, she is avoiding my gaze'' he asked him. 

''cause your a jerk to her, you were the one that ignored her first, your the one that decided to give y/n no breaks, ok so think she is the problem maybe you need a mirror'' he said to him before leaving. eijiro was confused and shocked. 

he didn't know that what orders he gave to y/n would hurt you. tho it's true that didn't see any thing in her. that doesn't excuse him from be a ass right now  a year later you did the same thing as last year. you took a dive into the ocean. that day the captain was actually the one who saw you dive in the water. 

he didn't know that you could swim or that you were a mermaid. so when you came back after having a swim ''y/n my office now'' he said ''what do you want?'' you asked him ''why did you dive into the ocean you could of drowned'' he said ''i can swim captain, you shouldn't care about what i do with my free time'' you said to him. 

as you went to leave the office. eijiro threw water on your head. the water turned you into a mermaid (''yep yep yep thats right my a mermaid take it in'') you lay there in mermaid in his office cabin. ''so your a mermaid and human?'' he asked ''yeah i am, it's not like it's changes anything'' you said to him ''right well let you change'' he said to you. 

you changed back into a human and left his office. he had no idea that he had two half human and half mermaid on board his ship as crew members. so after he found out he tried to nice to you. he wasn't as worried about you. but he was trying to change his attitude towards you. for the future of his crew mates and his ship. he didn't want a mutiny on board. 

3 year has past on the kirishima ship. captain eijiro tried his best to be nice to you and believe me it was hard when i tell you had he tried. he did his best. for apparently his best just wasn't enough for y/n to stay full time. she left for another 2 months. 

eijiro was annoyed and hurt cause he was trying to nice to you. especially you. he didn't know why he was trying so hard. maybe it was out of guilt. could that be it. he thought to himself. or maybe it was something else. maybe it wasn't cause of the guilt. maybe it was love. maybe he had feelings for the reader. for y/n ashido. 

another year went by as the crew went on their journey. y/n came back after 2 year of being in the ocean. when she came back she just went back to her job the next day. it was weird to see her back so soon and so well normal. it was weird. when eijiro found that she was back. all he wanted to do was see her. to tell her of his feelings and see if she liked him back. the honest reality is that she would say no to him and reject his confession. 

but he wasn't to give up that easily. when he got to see her. he called to his office. y/n stood there un knowing that eijiro her captain was going to confess his feelings to her. they talked for a while before he confessed. meanwhile the crew were outside the cabin listening in on the whole conversation between you and him. 

''what about you on about eijiro?'' you asked ''i like you y/n, i don't know why i do, i just do and i don't you to leave me'' he said ''what, is this a joke?, it's got to be, there is no way in hell you would ever have feelings for me'' you said to him ''please y/n i know you like me too, i heard that you use to have a crush on me or still do you have a crush on me'' he said ''how do you know that? where did you get that information?'' you asked him 

''mina told me, i'm sorry i asked her so she told me or was it sero who told me'' he said as she walked over to you '' i don't know how to take this information captain'' you said ''well maybe this might help. he walked over to you. he gently kissed your cheek. ''what about now?'' he asked you. ''i don't know eijiro how i feel about this'' you said to him. ''it's Eij, call that instead no more Eijiro or kirishima or captain'' he said. 

after that talk you and eijiro got a lot closer. him being the captain. he bumped you up to first mate. so you and him could spend more and more times as the years went on. he even let you take the helm duty. so you were in charge of the ship and all the crew including the your boy - friend Eij. he was right there beside you. to help you if got stuck or confused. 

he let one of his crew members take helm duty. as he took you back to his cabin "eiji I know your the captain but you shouldn't just leave like that" you said to as he pushes you up against the wall of the cabin "yeah I know that pebble but I rather be with you then be up on deck" he said to you as he kissed your neck "but eiji.... *he moved your pirate shirt aside.

he sank his sharp teeth into your collarbone*...ah.... eiji.. *as you as put your hands around his neck bringing him in "ah so you like my shark kisses don't you pebble huh?" he asked you with a smirk on his face "maybe I like it eiji" you said to him blushing as you look down "oh so you like it huh well then come with me" he said to you as he took your hand "where are you taking me?" you asked him "ah I don't know to a room" he said to you.

Captain eijirou took your hand and brought you to a room "go on open it'' he said to you as you did he pushes you into the room you see a bed you look at him kinda knowing what he wanted to do but you didn't want to say it incase its something else instead you spoke which was a big mistake ''eiji idk wont then hear us'' you said to him ''what's wrong pebble it will be fine ok hey look at me ok my crew already know we are a thing so you don't need to worry'' he said to you as he kissed you ''yeah your right eiji i guess'' you said to him. 

he got on the bed and sat beside you ''you know i love you right pebble'' he said to you ''yeah i know that i love you to eiji'' you said back to him ''then i know we haven't been together long since we became a couple but i want this and i want you'' he said to you as he took your hand in his ''i know eiji i want you too but........*you were about to continue but eijirou interrupted you* ..........''don't say anything pebble'' he said to you as he pushes you into the sheets as you both make out you and him end up having sex you and him lay there in each others arms.

after a while of lay there in bed together you heard a knock coming from the bedroom door you covered yourself while your pirate bf eijiro got dressed first then he walks over to the door and opens it to see crew member kaminari ''what is it kaminari?'' he asks him eiji shuts the door behind him to give you the space to get dressed again ''well we are almost heading towards [inset island] soon i just wanted to you that captain'' kaminari said to him ''do the others know of the schedule?'' he asked him. 

he moved out of the bedroom he closed the door behind him leaving you to get changed you could the hear their conversation ''yes captain they all know of schedule'' he said to him ''then get everything ready for docking at the habour'' he said to kaminari as he bow ''ay eaye captain'' he said to him as he told the others. meanwhile back in his bedroom you had gotten dressed and was now sitting on the bed you saw that your pirate bf forgot his pirate hat so while he wasn't hear you wear it for a while.

when your bf came back to the room to you see dressed sitting on his bed and wearing his pirate captains hat he smirks ''you look cute with that hat'' he said to you ''oh eiji i was just trying it on here you can have it back'' you said to him as you were about to take his pirate hat off your head he stops you and puts back on your head ''no keep it pebble it suits you better'' he said to you with wink ''oh ok eiji'' you said to him with a smile with blush ''oh ok lets go up on deck to the others pebble'' he said to you as he took your hand in his ''yeah ok eiji'' you said to him as you both walk out of the bedroom and went upstairs to the deck to see the crew looking at you and him.

you just blush and looked away as their captain eijirou took you upstairs to the balcony of the ship (fast-forward 20 minutes later) the kirishima pirate ship had reached the habour of [insert island] kaminari and deku helped with tieing the rope to the catwalk as the stairs to the catwalk was done some of the crew stayed behind on the ship to mind while remaining crew set off to the see the island as you were about to go off with your twin cousin mina. your pirate bf eijiro had took your hand in his as you blushed you hid your face with the pirate hat as mina teased you. (fast -forward 30 minutes later) the rest for the crew went back to the ship with mina, the first mate (you the reader) and your pirate bf captain eijirou kirishima back on to the ship and sent off again.

after a few more years (5 years) of dating and living on a ship and adventuring with your pirate bf eijiro and his pirate crew you and him decided to tie the knot and get married so you decided to have it on local island it wasn't the biggest wedding but you didn't really care as long as you are marrying the man you love you didn't care about anything else. the islanders and the crew were there to celebrate it and soon after that you, your newly wedded pirate husband eijirou and his crew went back to adventuring for more years. after while it was fun but you were definitely very much missing something so you confronted your husband one day about this you had knock on the door of his cabin ''pebble what's wrong?'' he asked you (you looked at him ''ah he's sweet to care about me'') ''well i wanted to ask you about something?'' you asked him ''ok what is it pebble?'' he asked you ''well i was wondering if you even idk wanted a family of our own just to think about'' you said to him.

''family? huh interesting id think i have thought about that before maybe why do you ask? do you want a family with me pebble is that what your asking?'' he asked you as he got up from his desk ''maybe i just think it would be nice have a family to have a little me or a little you with the man i loved and married'' you said to him ''ah gessh pebble i love you so much you know that right'' he said to you giggling ''yes i know that eiji'' you said to him ''then ok yeah lets start a family pebble i want that with you'' he said to you. so after that conversation you and him have been trying even anytime you have together you would trying to pregnant one day you and him were the only ones on the ship the crew decided to have a break and their captain was enough to let them go for couple of hours well thats what you thought so you and him were the bedroom.

you and him were just having a make out session that turned heated he pushed you back on to the sheets as he hovers over you he striped your pirate clothes that just left you in the under- wear as he kissed your body leaving hickeys on your neck to your collarbone to as he unclipped your bra letting your breasts free he pushed you back into the sheets he continued to kiss your breasts giving each one individually attention as he sucks and massages on your nipples then to your bridge to your stomach to your legs and thighs. left shark bites down your legs and thighs as you moaned from the bliss ''you really do like my shark kisses don't you pebble?'' he asked you as he continued to bite you. he spread your legs wide open and looking down at his prize as he shoves a finger into you p$$$$ he moves that finger inside you as he added two more fingers you moan and released on to his fingers as he pulls out and licks then clean "god for a mermaid damm pebble you taste so good" he said huskily to you. blushing immensely at what he said to you he had already gotten on his knees bringing you closer to his face. Eijiro blew at your p$$$$ you whimpered at his touch he chuckled as he grabbed your thighs in place as he slowly but teasily licked your fold with his tongue.

you had flinged your head back in pleasure and as eiji began to suck on your clit as he ate you out you had grabbed his red spiky hair with your right hand also tugging on his white pirate bandana moving him in as your left hand grabbed the pillow for support. Kiri got the message and nuzzled his tongue further into your p$$$$ as he continued eating you out as you moaned louder "ah! Ei ~ jr so ah good" he chuckles, making you shiver above him as you release again all over his face "I was right you really do taste good pebble" he said in your ear as hovered over you again. you kissed for while when your foot started to tug on his belt a little bit letting him you want to go further.

eijiro kisses you as he gets up and strips his pirate trousers and brief's off to let his 9 inch dick spring from it's confinement as you got up on your knees and crawled over to his friend. but he pushes you back '' oh no no pebble not this time'' he said to you as he push up back into the sheets. so you lay backdown on the bedsheets and spread your legs wide open for your bf eiji-kun. He hovers over you and traps your lips in a kiss "are you ready pebble" he said to you as he positions himself at your entrance "yes eiji-kun I ready daddy shark" you said to him with a smirk he starts to move not letting you get use to his size you gasp at his roughness "ah do you like that baby shark" he said into your ear you moaned loudly in his ear.

"ah yes Daddy shark" you moan he slammed into your p$$$$ again as you left deeper marks and scratches all down his back "you like how rough and hard I'm go into you don't you pebble?" he asked you as goes into even faster "ah yes! Daddy shark faster" you moaned and flinged your head back into the pillow. He pulls out of you suddenly before you could release your third organism as he changes your position. He moves you to be on top of him so basically cowgirl position as your rode and bounced on his dick as he continues pleasure you from below your boobs bouncing everytime he hit down on you ah! Yes! Daddy shark" you moaned out as you continue to bounce on him " oh do you like that don't you pebble?" he asks you from below you.

crew pov:
the remain crew that was left behind on the ship could hear noises coming rom their captains cabin so they went to see what the noise was the members in question were kaminari, sero and deku so they went into the captains cabin to see the bedroom part of the cabin was kinda open so kaminari went over to the door to see their captain eijirou and his wife y/n kirishima in bed fucking ''so what is it?'' sero asked him ''oh its our captain and his mermaid/human wife y/n do it in bed'' he said to him ''wait .. what .. there doing what...........'' he said before fainting to the floor of the cabin kaminari looks behind to see izuku fainted on the floor he smacks his face as he looks at sero ''here we go again seriously'' he said to him.

as he shuck his head as he went back to watching ''oh come on man why do you this every single time we talk about this?'' sero asked the fainting izuku on the floor of the captains cabin he looked up at kaminari ''yeah kami stop watching them and me over here lets take him out of here'' sero said to him as kaminari and sero help izuku out of the cabin to the deck they throw freezing cold water on to him ''oh come you didn't have to that to me'' he said to him as he shuck his now wet green curly hair ''what you were the one that fainted so we tried water and it worked after we said that our captain and his wife were having sex'' kaminari said to him ''oh shut up'' he said to him.

back in the bedroom he had suddenly changed his position again he fucks you from the side one hand on your left breast playing with nipple as his other hand lifted your leg up more as his dick moved in and out of you he saw a very small growing bulge starting to form in your stomach "hey pebble look at this?" he asked you "hmmm ah" you said to him as you felt him touch your stomach you look down to see that he was rubbing your stomach "look at this Bulge in your stomach see how well your taking my dick such a good little pebble aren't you baby shark" he said to you. You nodded and look away from him as his dick kept on moving in and out of your p$$$$ he chuckles as he changes his position once again he flippes you to be on your hands and knees in doggy style with your ass up in the air. He went back down on his knees as he licked your p$$$$ "ah nhg da~ ddy shark" you scream into the pillow he got back up and moves his dick back to your entrance he waits for a minute before shoving his dick into you.

"ah ngh" you scream even louder "yeah that's it pebble take it all" he said to you as he moves his dick into you at a unhuman speed while having his hardening quirk back on he filling up every inch of your p$$$$.

"scream my name again pebble" he said near your ear as he fingered you as his dick moved inside you.

"ah! Daddy shark " you moaned

He spanked your ass again "say it louder pebble" he ordered "ah daddy shark! daddy shark"

"again louder pebble" he said "ah! Daddy shark! Daddy shark! daddy shark"

"again pebble" he spanked you again even harder "ah! Daddy shark! Daddy shark! Daddy shark! daddy shark"

He thrusts into you even faster and harder into your p$$$$ he hitting your g-stop "ah! fuck! Yes! Da~ ah ~ddy shark! Yes! hit there again" you moaned into the pillow "ok baby shark" he said as he thrusted into you even more faster hitting and hitting your g-stop as he his free hand went down to your p$$$$ and just fingered you making go over the edge. He flinged you back around and you went back to giving him deep marks down his back "ah! Da ~ddy sha~rk?! I go~nna cum" you moaned "ah! Me too pebble" he said he grunted in your ear.

Eijiro felt his thrusts gets sloppier and sloppier "da ~ ah ~ ddy sha~rk cum in me" you moaned in his ear "as you want pebble" he said as he intertwined his hands with your hands. You and Kiri grunted and moaned as you felt each other release. You released your juices on to kiri and the bedsheets as kiri shot out his seeds into you and the bedsheets. He pulled out of you collapsing beside you on the bed sheets he pulled you into a hug as you both catched your breath back again "i love you my pebble" he said to you as he looked down at you in his arms you giggling "I love you too my captain" you said to your pirate husband eijirou had a nap together for a couple of hours (fast-forward to later) the rest of the crew had come back to the ship and so there was gossip about the captain and his wife. 

it didn't last long cause the eiji knew who it was cause here there voices outside the bedroom door. 9 weeks later you feel ill for reason and after going to a witch doctor with your husband you were pregnant with twins girls. your husband was happy that you pregnant i mean he was going to be a father to twins he was very happy about it. so throughout 9 months of pregnancy you had to visit the seas more cause mermaids actually give birth in the seas cause they need it to breath so you would go back and forward with the visits until one day you stopped visiting the ship cause you in labour you had to go back home a for while later when the mermaid nurse came in with the twins.

you go to hold them your first twin hamako l/n kirishima (meaning of the name ''child of the shore'') was full human so they created a bubble for her to breath in while she underwater with you and twin sister she had your eyes and had her dad's original black hair for her face features (she had your eyes, nose shape while she had her dad's lip, chin shape). while the second twin takara l/n kirishima (meaning of the name ''treasure'') was like you so half mermaid and half human she had your h/c and his red eyes after a month for her face features (she had your lip, chin while se had her dad's eye, nose shape) you went back to him with the twins you arrived at the ship to your husband ''eiji! hey crew'' you said to him and to his crew as they looked at you coming in near them with two new visitors/ recruits ''pebble you came back i missed you so much was everything ok?'' he asked you.

as he looked down at the two new young faces ''yes everything is thing but i have to new twin visitors for you and the crew to meet'' you said to him as look at your kids ''go on kids say a hello to your dad'' you said to him as they step out to greet their dad ''hello dad'' they said to him as they hugged him after they left to run around the ship as they played catch and case game as your husband looked at them having fun he smiled as he looked back to his wife you ''so these are the twins which one is which?'' he asked you as he looks back at them again to see them talking to the crew.

''ok well hamako is the one over there messing with hanta and katsuki who are over near the swords (meanwhile over at the pirate crew station hamako was talking to hanta and katsuki ''what are you looking at kid?'' katsuki asked her as he continued to clean and sharpen his sword ''pointy so cool'' she said to him as she watched him work on his sword he looked up at her ''huh what you say kid?'' he asked her hanta jumped into the conversation ''man i think is complimenting you on your sword cleaning ship and the fact that your sword is pointy'' hanta said to you ''oh is that so oh ok wanna hold my sword?'' he asked her she nodded as katsuki hand hamako the sword he told her how to use it in combat) *back to you and your husband eiji* and takara is the one over near izuku'' you said to him (meanwhile over near todoroki and denki station your daughter takara was talking to izuku ''i like your hair it looks so fluffy so do you like being a pirate?'' she asked him ''thank you i guess *izuku blushes at the compliment.

he looks back at her* yeah its fun but not easy'' he said to her ''so your the captain's the daughter your a VIP abroad this ship'' denki said to her ''yeah i am but i'm one of his daughters my twin sister is over there talking to those to you *she points towards hanta and katsuki* anyway captain why do you call him that? she asked him ''well he is a pirate captain after all'' izuku said to her) *back to you and your husband eiji* ''oh and before i forget eiji takara is like my she is half mermaid and half human and hamako is fully human'' you added as he nods you and your husband eiji walk over to the twins as he brought them to the helm as he spoke to his crew ''lads! my crew we have two new special guests abroad our ship today and they our my kids so behaviour yourself around them from now on'' he said to them ''ay eaye captain'' their all said back to him ''now kids you can go play but be careful'' you said to your kids ''ok momma'' they both said to you as they ran downstairs to play catch & case, adventure games abroad their dad's ship and talked to the crew members as you and your husband caught up in his cabin of the conversations and cuddles you both missed being together in each other arms.

through the years abroad the ship the twins messed with their dad's crew alot but mostly teased them it being mostly izuku and katsuki your twins loved them teasing them especially katsuki idk why but they just love it you think it just to get a reaction out of him other then that they never got into trouble well just yet that is. they both lived with their mom and dad abroad the ship and the crew your daughter takara and you had to take weekly trips to sea for breathing practice for her to be able to live in the sea and one land with her family while your husband eiji and your other daughter kamako had a dad and daughter bonding practice he taught her to fight like a pirate to everything like a pirate while her twin takara didn't really get it but soon learned that she is half pirate to so it was in her DNA to learn this stuff so she did get the hang of it eventually and after all of this your husband told story to the twins on he met their mom and how he fell in love with the sea or had a love for the sea.

Name of meaning
Hamako - child of the shore
Takara - treasure

The end
Word count: 55915
this pirate story was a long idea that i had and after searching for the right picture i found it idk the exact name of the twitter account but i'll out it down when i do. Hope you guys enjoy the story! See you guys in the next story ✌️