We make one thing.
A big fleece monster with an enormous mouth and eyes that don't quite agree with each other.
Monster Onesie started with a simple observation: the best costume is the one you never take off.
So we made a monster. Big fleece body, enormous mouth, eyes that don’t quite agree with each other — sized for real people, from teens to 6'1″ dads. It goes on for the party and stays on for the next three months of movie nights, cold mornings, and questionable group photos.
There are seven monsters: Swamp Green, Grape Fuzz, Coconut Cream, Cloud Blue, Midnight, Cherry, and Butterscotch. One mouth. Every onesie ships with its own free comb, for the tuft of hair on top — is it necessary? No. Is it included? Yes. Add the fuzzy slippers if your feet want in on it.
We believe in oversized on purpose, in washing machines that return your monster fluffier than before, and in 30 days to decide with no interrogation. We believe a matching set can ruin a group photo in the best possible way.
Be the monster.


Built to be lived in.
Oversized through the body, long in the arm, sized by height rather than by letter.
Shop the monster →One product, on purpose
No seasonal range, no forty variations of the same idea. One onesie, seven colors, done properly.
Made to survive the wash
Coral fleece that fluffs back instead of matting. It is meant to be worn constantly, not saved for one night.
30 days to decide
Not feeling it? Send it back within 30 days of delivery. No forms, no interrogation, no hard feelings.
Monsters hear about drops first.
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