Cat (K-pop Demon Hunter) Costume
Unleash your inner derpy, demon-hunting feline companion in cozy style.
The Cat (often lovingly referred to as Derpy) is the quirky, fan-favorite feline companion from the hit series K-pop Demon Hunters. Fans adore this character for its hilarious, wide-eyed expression and cozy aesthetic, making it a popular choice for comfortable cosplay. The look centers around a plush cat onesie customized with a signature goofy face.
- Difficulty
- Easy
- Time
- ~30 min
- Budget
- $25–60
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See yourself as Cat (K-pop Demon Hunter)
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What you need for a Cat (K-pop Demon Hunter) costume
Short on time? Buy it ready-made
Spirit Halloween sells the complete Cat (K-pop Demon Hunter) costume — one box instead of 5 pieces.
Black or dark grey cat onesie
A soft, hooded fleece jumpsuit with attached cat ears and a tail.
DIY: Use a plain black hooded sweatshirt and matching sweatpants.
Mismatched felt sheets
White, black, and yellow felt sheets to construct the oversized, goofy cartoon eyes.
DIY: Cut the eye shapes out of colored cardstock or stiff fabric.
Pink felt sheet
A small sheet of pink felt to create the inner ear lining and a tiny nose.
DIY: Use pink fabric markers or acrylic paint directly on the hood.
Fabric glue or safety pins
Used to securely attach the felt facial features to the hood of the onesie.
DIY: Hand-sew the felt pieces onto the hood with a basic running stitch.
Black sneakers
Simple, comfortable black canvas or athletic shoes.
DIY: Any dark-colored socks or slippers if wearing the costume indoors.
Rather not assemble it? See ready-made Cat (K-pop Demon Hunter) costumes at Spirit Halloween ↗
How to put it together
- 1
Lay the black cat onesie flat on a clean workspace with the hood spread out.
- 2
Cut two large, unequal circles from the white felt to serve as the base of the derpy eyes.
- 3
Cut smaller black and yellow circles for the pupils, positioning them pointing in slightly different directions to capture the signature goofy expression.
- 4
Glue or pin the assembled felt eyes onto the front of the hood, just above the opening.
- 5
Cut two pink felt triangles and attach them to the front of the hood's built-in cat ears.
- 6
Add a small pink felt triangle in the center of the hood just below the eyes to serve as the nose.
- 7
Put on the onesie, zip it up, pull the hood over your head, and step into your black sneakers.
Makeup & hair
Keep your hair completely tucked inside the hood. If desired, use black eyeliner to draw a simple cat nose and whiskers on your face for extra detail when the hood is down.
Cat (K-pop Demon Hunter) for couples, groups, kids & more
- couples
- Pair up with Rumi wearing her signature cat-and-star patterned pajamas.
- group
- Form a squad with Rumi, other K-pop Demon Hunters, and a few colorful, stylized demons.
- kids
- Use a child-sized black cat onesie and follow the same felt eye customization steps.
- Plus size
- A loose-fitting, unisex fleece onesie provides an incredibly comfortable and forgiving fit for all body types.
- pet
- Dress your dog or cat in a simple black pet hoodie decorated with small felt star patches.
More ways people search for this costume
The most-searched variations of “Cat (K-pop Demon Hunter) costume”, and how this look adapts to each.
K-pop demon hunter cat costume
- Dress your dog or cat in a simple black pet hoodie decorated with small felt star patches.
Tips
- Make the felt eyes intentionally uneven and misaligned to perfectly capture the character's derpy look.
- Fleece onesies can get very warm, so wear a lightweight t-shirt and shorts underneath.
- This cozy outfit is perfect for cold-weather trick-or-treating or outdoor conventions.
Cat (K-pop Demon Hunter) costume FAQ
- Who is the cat in K-pop Demon Hunters?
- It is the quirky, fan-favorite feline companion (often called Derpy) that accompanies Rumi and the other hunters on their missions.
- How do I make the cat face look authentic?
- The key is the eyes: cut out large, unequal circles of white felt, add smaller black pupils pointing in slightly different directions, and glue them to the hood.
- Is this costume comfortable for walking around?
- Yes, using a fleece onesie makes it one of the most comfortable, warm, and mobile costumes you can wear.
Did you know? Derpy the Cat became an instant fan favorite due to its hilarious contrast with the high-energy, stylish K-pop choreography in the series.