The supermodel's giant invertebrate get-up was, unsurprisingly, a complicated undertaking.
The 20-year-old singer posted a photo of her with 31-year-old Jesse Rutherford — and seemed to troll critics of their age gap.
"I don't want to let my Halloween fans down, or myself," said Klum of the costume, which she said took several months to make.
The Skims founder was able to poke fun at herself and shared a hilarious photo.
"No greater bastion of parenting desperation than the Halloween costume aisle on October 31."
Fun and clever ideas for you, your partner and your baby boo
From a mermaid to a postal worker, here are eight adorable costumes perfect for your fur-baby.
Original costume ideas for you and your partner that are scary-good.
Who hasn't wanted to dress up as a pack of birth control pills or an empty roll of toilet paper for Halloween?