How We Built a Baby Saja Costume (Without the Meltdown)

Marcus
2026-03-29T11:07:02+02:00

I was holding a detached, highly synthetic faux-collar in my left hand while my eleven-month-old son actively tried to eat a teal polyester wig. This was iteration one of the baby Saja outfit, ordered at 2 AM from a drop-shipping site my wife explicitly told me to avoid. The "dickey" collar was supposed to simulate a button-down shirt under a sweater without the extra layer, but instead, it just slid around his neck like a defective gasket while he screamed in what I can only assume was deep sensory agony. He was sweating profusely. I was sweating profusely. We were ten minutes into trying on this store-bought nightmare, and the system had completely crashed.

If you've been living under a rock, or if you just don't have a toddler hijacking your streaming algorithms, K-Pop Demon Hunters is an animated movie that has completely taken over our household. Specifically, my son is obsessed with Baby Saja, the lead rapper of the antagonist demon boy band. Saja's whole gimmick is that he looks incredibly cute but aggressively drinks hot sauce out of a standard infant bottle during his rap solos. Because my son also possesses this exact chaotic, unpredictable energy, we decided this was the year to figure out a baby saja costume. But after the drop-shipped polyester disaster, I realized I had to approach this like a software engineer: scrap the proprietary garbage, source open-source materials, and build the baby saja costume for kids using actual human clothes.

The great cultural appropriation panic of Tuesday night

Before we even started assembling the wardrobe components, my wife Sarah and I had a minor existential crisis staring at our incredibly white, very pale Portland baby. He loves the Saja Boys tracks, he bounces his knees to the beat, but we suddenly found ourselves panic-googling whether dressing him as a Korean animated demon idol was cultural appropriation. I spent three hours going down a rabbit hole of sociological articles when I should have been sleeping.

Apparently, according to the creator of the film and a bunch of sociologists I read about, it's actually completely fine to cosplay these characters regardless of your background. The creator practically begged kids to wear the outfits, which felt like a solid green light. However, Sarah very quickly corrected my understanding of the boundaries, pointing out that while the clothes are fair game, attempting to alter our kid's facial features with makeup is a massive, non-negotiable hard line that crosses immediately into racism. We obviously weren't planning on putting eyeliner on an 11-month-old anyway because he won't even let me wipe avocado off his chin without thrashing like a captured alligator, but it was good to establish the parameters. I also learned that the characters' outfits are loose nods to traditional Korean underworld messengers, which is a frankly terrifying and metal concept to wrap around a baby who still cries when the vacuum cleaner turns on.

Troubleshooting the toddler wig situation

Let me just say that wigs for infants are a fundamental design flaw. They defy physics, logic, and basic human empathy. The store-bought teal wig I originally purchased was basically a net of itchy, highly flammable plastic fibers that smelled faintly of industrial solvents. I read the warning tag, and it essentially implied the thing would spontaneously combust if exposed to direct sunlight.

Beyond the safety hazard, there's the sensory data. My son grabbed the wig off his head in exactly 4.2 seconds and threw it across the living room. I tried to put it back on him, and he looked at me with a level of betrayal I haven't seen since I accidentally ate his last blueberry. Wigs on babies just don't work unless your kid has the idle patience of a monk, which mine doesn't. He is constantly moving, constantly rubbing his head on the carpet, and constantly trying to pull his own ears off. A wig was never going to survive.

Instead of forcing the issue and dealing with a localized meltdown, we decided to completely abandon the anime hair and just rely on the character's iconic hat to carry the visual weight of the outfit.

As for the pants, we just bought a pair of dark purple skinny jeans from a thrift store and called it a day.

The Bill of Materials (BOM) for a breathable build

If you're trying to keep your kid from having a total core meltdown in this outfit, you'll probably want to ditch the cheap synthetic costumes entirely and stick to a modular build using standard, breathable layers.

The Hat: A mustard yellow newsboy cap, deployed in reverse orientation. We safety-pinned a little blue fake forget-me-not flower to the side.

The Base Layer: A highly breathable cotton onesie (more on my obsessive research regarding this below).

The Outerwear: A lightweight pink sweater.

The Bottoms: Dark purple or royal blue pants.

The Footwear: Classic white sneakers. We found some with pink soles, which felt like a massive victory.

The Prop: A sealed baby bottle with fake hot sauce.

Explore our organic baby clothes collection if you're trying to build costumes out of actual breathable fabrics instead of plastic bags that trap heat like a greenhouse.

Base layers and the thermal dynamics of knitwear

The core of the Baby Saja look is a pink sweater layered over a crisp white collared shirt. Here's the problem: an 11-month-old's internal thermostat is basically a faulty line of code. Our pediatrician casually mentioned during a checkup that babies process heat entirely differently than we do, which I interpret as their cooling firmware being highly defective. If you put two long-sleeve layers—a woven collared shirt and a knit sweater—on an infant in a heated Pacific Northwest house, they'll overheat immediately and start screaming.

Since the fake "dickey" collar was a catastrophic failure, I needed a base layer that provided the illusion of a shirt without the thermal load. I ended up using the Organic Cotton Baby Bodysuit Sleeveless Infant Onesie underneath a very thin pink argyle sweater. This bodysuit is honestly my favorite piece of clothing in his dresser right now because it actually breathes, and the elastane in the neck means I don't feel like I'm dislocating his nose when I pull it over his disproportionately large head. It absorbed whatever sweat he was generating while wrestling with the dog, and the sleeveless design meant his arms weren't suffocating under the sweater sleeves. We completely skipped the rigid collar look because, frankly, comfort is more important than strict character accuracy when your subject can't speak and communicates displeasure by throwing hard plastic blocks at your shins.

Prop management and the hot sauce logistics

Saja's signature accessory is the baby bottle full of hot sauce. Building this prop required actual garage engineering. I initially thought about just putting red Gatorade in a normal bottle, but then I remembered my son's current favorite activity is holding bottles upside down and shaking them violently to test the structural integrity of the nipple valve.

I eventually took an old, scratched shatterproof plastic bottle we were going to recycle, filled it with water and twenty drops of red food coloring, and sealed the absolute life out of it. I'm talking marine-grade silicone sealant on the threads of the collar and superglue inside the nipple hole. I drop-tested it on our hardwood floor three times to make sure zero leakage, because red dye on a light pink sweater would permanently corrupt the entire save file of this costume.

The sealed bottle looked amazing, but there was a secondary bug I hadn't anticipated. Because he's teething aggressively, he immediately tried to chew on the hard plastic cap of the sealed bottle. He has exactly four teeth, they're razor-sharp, and I was genuinely worried he was going to crack the plastic or hurt his gums. During the actual Halloween party we went to, I ended up taking the hot sauce bottle away and swapping it for his Panda Teether Silicone Baby Bamboo Chew Toy. It's food-grade silicone, totally non-toxic, and handles his aggressive gnawing perfectly. Is a bamboo-munching panda strictly canon in the K-Pop Demon Hunters universe? No. Did it stop him from screaming while we took photos? Yes. Sometimes you've to push a hotfix to production even if it doesn't match the design specs.

Containment strategies while getting dressed

Putting all these layers—the onesie, the pants, the sweater, the socks, the shoes, the hat—onto an 11-month-old requires a static environment. My son currently views diaper changes and outfit swaps as high-stakes wrestling matches where his objective is to barrel-roll off the changing table at maximum velocity.

To keep him contained while I desperately tried to pull the pink sweater over his arms, I slid him under his Wooden Baby Gym. Honestly, this thing was a magical distraction device when he was four months old, but at eleven months, it's just okay. He's way too big for it now and mostly just uses the sturdy A-frame to pull himself up into a standing position, treating the whole structure like a gym pull-up bar while trying to rip the hanging wooden elephant off its tether. Still, the loud clacking of the wooden rings bought me exactly 45 seconds of relative stillness—just enough time to jam the yellow newsboy cap on his head backward before he realized what was happening and tried to evade capture.

In the end, the DIY approach took way more mental bandwidth than just clicking "buy" on a Halloween website, but the resulting outfit was infinitely better. He was comfortable, he didn't overheat, and the clothes are actually functional pieces we can mix into his normal wardrobe (well, maybe not the bright yellow backwards hat, but the rest of it). Parenting is mostly just a series of poorly documented trial-and-error experiments anyway. At least this one resulted in a really good Instagram photo before he spit up on the sweater.

If you're still in the trenches of teething while trying to survive costume season, grab the Panda Teether and maybe save yourself a 3 AM meltdown.

FAQ: Debugging the Saja Look

Is it okay to skip the wig for a baby saja costume?

Oh my god, yes. Skip the wig. Unless you want your kid scratching their scalp raw and crying the entire time, just use the yellow backwards cap. I spent thirty bucks on a teal synthetic wig that was worn for exactly four seconds before it became a chew toy for our dog. The hat is more than enough to sell the character.

How do I make the hot sauce bottle without it leaking everywhere?

Don't trust the natural seal of a baby bottle if you're putting food coloring in it. Your kid will find a way to break it. I used waterproof silicone sealant around the screw threads and superglue inside the rubber nipple. It basically turned the bottle into a permanent, solid brick of plastic. Just make sure you use a shatterproof BPA-free bottle so if they chuck it at the pavement, it doesn't explode into glass shrapnel.

Won't my baby overheat with a collared shirt and a sweater?

Probably, which is why I completely faked it. I couldn't handle the weird detached fake collars from the cheap costumes, so I just put a very thin, breathable organic cotton sleeveless onesie under a lightweight sweater. Nobody can tell he doesn't have a collar on, and more importantly, he didn't turn into a sweaty, screaming tomato.

Can I use normal clothes for this instead of a costume in a bag?

That's literally the only way I'll ever do this again. The bagged costumes are made of terrible, itchy materials that don't breathe. Just go to a thrift store or buy normal baby clothes—a pink sweater, purple pants, white shoes. It looks way better, the zippers honestly work, and your kid can wear the pants again on a random Tuesday.

Is the hot sauce bottle safe for them to chew on?

If you seal a hard plastic bottle, the cap isn't great for teething babies. My kid tried to gnaw on the plastic ring and it sounded like he was going to chip a tooth. If your baby is actively teething, ditch the prop bottle and just hand them a silicone teether for the actual trick-or-treating part. We used a panda one and nobody questioned it.