Sea Witch Aesthetic Decor: How to Create a Dark Siren + Mermaidcore Oasis in Your Apartment
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Want to make your apartment feel like a dark deep sea retreat filled with witchy decor, moody ambiance, and powerful sea witch energy? Then you might want to explore the sea witch aesthetic with me!
In this post, I’m showing you how to bring the sea witch decor look into your space with interior styling ideas that are equal parts enchanting and eerie. Think dark mermaid aesthetic meets underwater coziness - a place where you can get nice and comfy in peaceful, aquatic bliss. 🤌🧜♀️
Whether you're drawn to mermaidcore, want some good witchy decor ideas, or just love anything with a touch of fantasy aesthetic, this post (and its sister YouTube video) is full of inspiration to help you style your apartment like a true dark siren.
So if you want to create a space that feels like your own underwater sanctuary, read on!
Would you rather watch than read? Here’s the video! ↓
Do you remember going to the pool as a kid, playing mermaids with your friends? And you’d vividly describe your imaginary mermaid hair, the color of your fin scales, and the style of your (probably age-inappropriate) seashell top?
When we were innocent, sweet little children, we were mermaids. Now, as a full-grown millennial in 2025, I must admit… that my sea witch era is well underway. Which, frankly… is hot.
Because instead of chasing princes and losing my voice in the process, I like the idea of just living alone in my own little deep sea cave, doing my own thing, and maybe surfacing every now and again to lead a few silly men to their doom. 🙃
So the sea witch aesthetic is pretty appealing to me. Now let’s talk about what it is!
What is the Sea Witch Aesthetic?
The sea witch aesthetic is exactly how it sounds; it draws upon the folklore, mythology, and the visual language of sea witches, mermaids, sirens. It's a style that dives deep into the dark depths of the sea and dredges up nautical visual elements like seashells, fishing nets, shipwrecked detritus, oysters, and raw pearls.
It's moonlight shimmering on the black nighttime ocean. It's Lovecraftian tentacles. It's a style that represents something powerful and dark and seductive and a little dangerous. And when you implement the spirit of sea witchery in your decor, it's a way to feel that sense of power in a world where it's very easy to feel powerless.
If you can carve out a little slice of the world for yourself in your apartment in which you can feel like an all-powerful sea witch, then by all means, let's do it!
But how do we do it in our little rental apartments? That's always the question, isn't it?
So now I'm going to give you some ideas on how you can incorporate the sea witch aesthetic into your space!
1. Sea Witch Bust
This sea witch bust is an obvious choice for this look. I’ll admit, it's a little on the nose, but I mean… look at her. She's beautiful, she has a commanding presence, her hair is tentacles… She looks like she could rule over the seven seas, but instead, her kingdom would be your shelf and your other decor pieces, her subjects.
She would add an instant sense of feminine power to a room, which to me is really what the sea witch aesthetic is all about.
2. Hand-Painted Sea Shell
Then of course, seashells are a core part of this look. This artist on Etsy hand-paints seashells with beautiful art, and I mean… this is about as sea witchy as it gets. She exudes elegance and strength, but also some sadness, like she's seen a little too much of the world and she's disappointed. Honestly, same girl.
I'm into anything that conveys basically the opposite of "Live Laugh Love" decor. And this is more of a "Languish Lament Lie Down" piece; a meme that I find so much more relatable.
Not to be a downer, but I do be languishing. And I'd love to languish with this beauty as part of my decor!
3. Vintage Shell Flower Tree
How cool is this piece? The petals are made of real shells, as well as the base. This would be an example of a less direct way to do the sea witch aesthetic; it references the ocean and looks like something that could be owned by a sea witch or mermaid, but it's not a literal depiction of a sea witch like the last two pieces of decor I’ve covered here. It's more interpretive.
Like with all the more niche genre styles I talk about, it's all about the dance between literal and interpretive decor. Balancing the two is how you keep things elevated and stylish, and avoid the cheesy party theme look.
This shell sculpture would add a touch of elegance, as well as a more subtle nod to the sea witch theme.
4. Nautical Collage Pages
These little collage pages would bring a different kind of elegance, more of an 1800s scholarly dark academia vibe. They look like they could be pages torn from an old captain's log, only this captain saw all kinds of crazy shit at sea… and he was driven mad by the fact that he was the only one who saw mermaids and sea beasts, and these pages are the remnants of a mind that was either disturbed or enlightened. Or both.
Maybe it says something about my mind that this is the story I attached to something as simple as scrapbook materials, haha. I am the one who's either disturbed or enlightened. Or both. 🙃
But remember what I always say about interior styling of any kind: it's all about storytelling, especially when it comes to these more fantasy-driven looks. You want a piece of decor to summon a crazy-ass story in your head. That's what the best pieces of decor do.
And maybe these are intended for journaling and collaging, but I think you could DIY some really cool decor with these pages. You could arrange them together in one frame, or you could frame them individually to add to the gaps of a gallery wall. Or maybe just put one in a frame and add it to a shelf styling arrangement.
They’re very versatile, and it's just up to your creativity to decide what to do with them!
5. Glass Float String Lights
Like with any interior style, in my opinion, there's always room for fairy lights. And I found a couple options with a more nautical twist to them, so they're not your average string lights.
These ones look like the glass floats fishermen use to keep their nets from sinking, which is a classic seafaring visual trope. And I love how the glass would magnify the sparkle of the lights and just make things feel a little more magical in a room.
6. Oyster String Lights
And then these oyster string lights are so pretty. I love how the oyster shells amplify the glowiness of each light. They're like perfect little stages for the lights to shine extra bright.
I know I've made my pro-fairy-lights agenda very clear in my videos, so I might be biased, but it was cool to find a couple options that had a little bit more of a unique take on them!
7. Vintage Bottles
Bottles are another perfect fit for this look, as they’re a common trope in the visual canon of sea lore; messages in a bottle, model ships in a bottle, bottles of booze for bored sailors… bottles are a common accessory in stories of the sea.
And these look like they could have been collected from the aftermath of a shipwreck, don’t you think?
8. Celestial Bottles
Then on the other hand, you could go with a more whimsical bottle like these. They look like enchanted potion bottles fit for a sea witch, with a mystical vibe that looks as though you'd acquire the powers of the moon and be able to control the tides if you drink from them. A very sea witchy thing to do.
9. Sea Shell Pillow
I almost feel like a seashell-shaped pillow like this is obligatory for this style. It's just a no-brainer, and it would make a nice centerpiece for the pillow styling on a bed. It would also add a touch of almost Art Deco glamour, so it doesn't have to just be a sea reference!
10. Octopus Pillows
And then these octopus pillows would also be a cool addition to a sea witchy room. They do almost veer into cheesy territory, because yes, they are quite on the nose. But at the same time, I like the iridescent look of the octopi, and they would bring a nice pop of turquoise to a room. I think they could look awesome if they're surrounded by good styling choices, which you'll see an example of later in this post when I show you the bedroom design I created for this look!
11. Moon Light
This moon light is so perfect for this style. I’m personally a sucker for moon imagery in general, and it's actually a very good fit for a style that is so intertwined with the ocean—you know, with the moon's connection to the tides. It would bring such a vibey, otherworldly atmosphere to a room.
And I don't know about you, but it makes me think of these lyrics from "Moonlight Drive" by The Doors: "Let's swim to the moon, let's climb through the tide, penetrate the evening that the city sleeps to hide." It just takes me to that poetic headspace, you know? And that's always a good sign. If a piece of decor puts poetry or rock and roll of any kind in my head, then I'm going to like it.
12. Seashell Sconce
These shell sconces would bring such a pretty touch of aquatic glamour to a sea witchy room, with their almost liquid-looking glass. So stunning.
And to my fellow Legend of Zelda fans out there—doesn't this look like the kind of lighting you find in Zora's Domain? I mean, surely I am not the only one who sees that. Zora's Domain is peak sea witch/mermaid aesthetic, by the way. And I'd be lying if I said I wasn't consciously inspired by the Zora culture while shopping for my sea witch aesthetic video.
Legend of Zelda geekery aside, these sconces would be such a lovely addition to not only a sea witch aesthetic room, but really any style of room!
13. Seashell Chandelier
Another piece of lighting that would be so perfect for this look - and would also make a big visual statement - is this chandelier made of shells. In case this hasn't been made clear, you can really go all out with seashells when it comes to the sea witch aesthetic. And this chandelier would be a beautiful way to do that!
And even though it's a pretty dramatic statement, it's actually kind of a subtle way to incorporate shells. Because from far away, they could be anything. This could be a beaded chandelier at first glance, but when you get closer, you discover they are indeed shells. And little moments of realization like this are always a nice touch. They make your interior styling more of an experience rather than just pretty to look at.
14. Seashell + Pearl Lamp
For something smaller and easier to implement in your space (without the labor and heavy lifting of installing a full-blown light fixture), there's this little shell lamp that you can place on a nightstand or a desk just as a smaller touch.
It may be a small touch, but it really blatantly conveys the sea witch look. It's kind of the opposite of the shell chandelier, which was a big piece with a more subtle use of shells.
And I like that this has a bit of a playfulness to it - almost a cartoonish quality. I mean, who wouldn't want a glowing oyster pearl just vibing away on your nightstand as you relax in bed?
15. Dark Mermaid Wall Art
I love this dark, moody mermaid piece. Brooding in the moonlight is such a mood. I mean, I'd do it more often myself if these Seattle clouds would move out of my way.
But the mermaid (or sea witch? Siren?) in this piece strikes me as someone who could move clouds and tides and summon the moon whenever she wants. She's 100% that sea witch.
And as a piece of decor, I think she'd bring so much depth, emotion, and power to a room, especially if you're going for a moody, dark decor look.
16. Ship + Kraken Wall Art
For a little bit more of a Lovecraftian flavor, there's this piece of wall art depicting Kraken tentacles attacking a ship. I'd like to think that the mermaid in the last piece turns into this monster when she gets angry, sprouting tentacles and showing no quarter to sailors who dare trespass on her waters. That could be a fun visual storytelling through line if you happen to get both pieces.
By itself, I love the old vintage drawing look to this piece. It's timeless. And I have to admit that its sense of impending doom is appealing to me, personally.
17. Nautical Gallery Wall Set
Another option for wall art, especially if you're interested in doing a gallery wall for the sea witch aesthetic, would be this set. Now generally, I think a gallery wall, and any individual pieces of art, should ideally be collected over time. But sets like these can be a nice budget-friendly way to jumpstart your wall art situation, especially in an apartment where you might be there for just a year or so, and who knows what your wall space will look like in your next rental.
Something like this is just nice and accessible for us apartment dwellers who don't really have the luxury of permanence that owning a home offers. And these really are perfect for the sea witch style. It'd be fun to try different variations and experiment, while cohesiveness is guaranteed. It's like a cohesive gallery-wall-in-a-box that’s also on theme for the sea witch aesthetic.
18. Peel and Stick Wallpaper
You could also do a peel-and-stick wallpaper statement wall for the sea witch decor look. I love how this wallpaper gives an abstract appearance of the ocean. It would make a room feel like it was plunged underwater, and there's a sense of movement here that looks like ripples and waves, or maybe a zoomed-in view of a tidal pool.
It would also be a beautiful dark decor statement aside from the sea witch aesthetic. So if you wanted to switch your styling up away from sea witchery at some point, this wallpaper is versatile enough to work with lots of styles!
Sea Witchery Bedroom Design
Now let's see how some of the decor pieces could come together in a bedroom design I created!
Doesn't this look like an underwater sanctuary? It's dark and mysterious, but also pretty cozy-looking. Sure, a certain level of foreboding should be present in any witch aesthetic room, but that doesn't mean we can't be cozy too!
And you'll see that I've included some additional elements to complete the bedroom, like these nightstands that look like you could have found them in the captain's quarters of an old ship, this rug that kind of looks like the sea at night with flecks of moonlight shimmering off the black water, this shell-shaped headboard paired with teal bedding, and this dresser with a design that looks like fish scales.
I also found these octopus knobs as an added little detail, because the knobs the dresser comes with are kind of lame, in my opinion, and don't really go with this style.
And I will say, this is definitely a pretty exaggerated take on a sea witch room. I do think it's very pretty and elegant, but like I said earlier, we don't want to be too heavy-handed with the literal sea witch stuff.
But on the other hand, I like to go all out with these designs I create for videos because it helps to get the style across. And in this more realistic rendering of my design, I think it looks pretty lovely:
Overall, I like the oceanic drama going on here. It's like an enchanting boudoir that exists in the depths of the sea where it's nice and quiet and peaceful, and you can block out the chaos of the world. It's an escape where we can have our friends over and play sea witches as full-grown adults—like we did with mermaids as kids.
Only instead of vividly describing our mermaid hair and fin, and spinning a story about finding a handsome prince, we'd vividly describe the strength of our tentacles and scheme about ways to topple the patriarchy.
Love that for us. 😉
If you want more fantasy aesthetic decor ideas, watch this YouTube video playlist of mine! It has fairycore, hobbitcore, cottagecore, dark academia, light academia, and witch aesthetic videos I’ve created, so if you're into this fantasy stuff, you'll definitely want to check this playlist out:
