Luffy

-this little cinnamon roll will have you by his side all day

-the current island you were on would suffice for celebrating; he'd take you to one of the restraunts (complementary of Sanji)

-he doesn't understand some aspects of valentines day, but thanks to Sanji, knows the basics.

Sanji

-this holiday is one of the love cooks specialties, if you're with him during this time,be prepared for all surprises.

-he would wake you up with a sweet little kiss, telling you happy valentines day, and promptly give you some big bouquet of flowers.

-he would cook you (and the crew) a special breakfast made up of heart shaped chocolate chip pancakes with whatever you'd like on it, and give you a valentines card.

-he'd surprise you that evening by giving you a large box of chocolate, stuffed animals galore, and sessy sinful love time (͡° ͜ʖ ͡°)

Zoro

-he'd probably forget at first to be honest; he doesn't really keep track of holiday dates.

-he would come around once you'd wish him a happy valentines day; then he'd be embarrassed.

-he'd make sure to make it up by doing whatever you'd like for the rest of the day (as long as he didn't have to train as long)

Usopp

-most likely didn't go to sleep the previous night because he was tinkering around with a gift.

-that morning after breakfast, he gave you a little tinker toy that as all cool because he made it.

-he would be sure to keep things as normal as they would be; despite being the awkward little guy he is.

Franky

-he'd make sure you had a super valentines day!

-he would probably have a mini firework display for you set up confessing all of his lovely sentiments.

-he'd want to be rewarded for his efforts; get ready for the robo dick.

Robin

-she'd have a cute little lunch set up; a nice little card and candy for you.

-she'd make sure to do everything she could for you that day, making sure you wouldn't have to lift a finger.

-when it would all end, the two of you would cuddle under the stars on the deck; her whispering sentiments of love every so often.

Nami

-Nami would most likely be ready to get a v-day gift from you before you got yours.

-she'd wait for you to give her the card, candy, etc before she unveiled her own; much to your satisfaction.

-later that night she'd be very giving, letting you do as you please. Wink wink.

Chopper

-this little munchkin of fluff would most likely hand draw you a card with a little heart on it. Sobs. Adorable.

-he'd let you carry him wherever you went, letting you nuzzle into his warm and soft floof when needed.

-he'd be making shy accusations of love throughout the day, stuttering through some. (All)

Law

-law really isn't one for valentines day, despite the nickname.

-he would cuddle with you when he was available, letting you talk about whatever, humming him to a smile.

-he would wait until later to unveil his surprise; which ends up being the same every year to your pleasure sin sin.

Shanks

-shanks would most likely be the most excited for this specific day; he knows what he wants.

-he'd be giving you sweet pecks all over your face through the day. Oh you're reading? Kiss. You're about to go to the store? Kiss. You're about to take a bath? Let me hop in with you.

-he'd make it one of the most memorable days of your life; right after your birthday of course. Wink wonk

Buggy

-this ring around clown will be all over you, today is one of the flashiest days of course!

-he'll make sure to get you the best he can; flowers? Here you are! Are you hungry? Let me get some food for you! You're cold? Here's a teddy to keep you warm!

-after all the festivities, it's onto the real fun. You've heard of the circus, but now the circus is coming to your town

Ace

-lazy freckled baby is going to be holding you especially close that morning, warmth is strong with this one.

-he'll give a lazy "happy val day" and pull you on top of him, promptly playing with your hair.

-this cinnamon roll will follow you around like a list puppy the whole day, everywhere. And you'll love it.

Marco

-Pineapple birb would have gotten you up especially early that morning to watch the sunrise on the Moby.

-you'd be wrapped up in a nice big blanket, his arm wrapped around your waist. He'd have his head on top of yours, whispering sweet little I love you'd throughout the while experience.

-by the time breakfast rolls around, he'd carry you in himself and sit you on his lap as you enjoyed your breaky.

Thatch

-this cinnabun honey kins would treat you as royalty; even more so.

-he'd cook you the best breakfast, lunch, dinner, and your favorite dessert just to see that smile of yours; and that's all he needs.

-but would he let you go without? Oh no no. Expect kisses, hugs, cuddles! He'd buy you the finest chocolate, only the best for his own.

Rocinante

-this...angel will make your heart burst.

-he'd try to make you food, but would ultimately end up burning it. And after sorrow filled apologies he would cuddle you to death in his floof coat.

-he'd repeatedly tell you over and over how much he loves you, adores you, treasures your existence; you'll feel like the most wanted person in the world.

Doucheflamingo

-unlike his cinnamon brother, this sinful pink floof will look at the sexual aspects alone.

-expect a few nurturing words of encouragement. "Mm, yes happy valentines day, what did you get little old me?" "Oh, yes that is lovely mfufu."

-Dofla will pleasure you beyond belief, despite the loss of loving words, He'd make it up in actions; sinful actions.

Mihawk

-this birb would be one of the normal of the three daddies, he'd have a nice dinner planned, a evening alone, and a few presents for you as well.

-he'd have a nice layout of food for you to your own taste, a bottle of wine centering the table.

-you'd get a rather loving and doting card, written by hand to your own amusement and surprise.

Crocodile

-he doesn't like holidays really, but this one he'd take to heart. Just for you.

-he'd make sure to get you the biggest, best tasting, flashy and expensive things he could. He'll make everyone else look bad, much to his own personal satisfaction (and mine too)

-What did you say? You wanted a gigantic stuffed bear twice the size of you? Wait right there dear while I go get it for you. This'll be a day where he'll splurge rarely on anything and everything you want or look like you want.

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If you want a headcanon for v day of any other character let me know