Pictures and videos of the stylish simian, who somehow let himself out of a parked car and wandered outside the store, have popped up in news outlets ranging from the Mediterranean island of Malta to Melbourne, Australia and beyond.
And the rhesus monkey — decked out in a tiny tan coat — is soaking up his 15 minute of fame on social media, where the Twitterverse pounced on shots of the puzzled-looking animal.
By Monday Darwin had earned at least two mock Twitter accounts and his own hashtag, in addition to countless photoshopped images.
"#IkeaMonkey Darwin exhibited all the major steps of evolution: Complex cerebral activity, bipedal walking, Ikea shopping," one user tweeted.
Many cheered the five-month-old monkey's fashion cred.
"Can't wait to dish critique on that divine Russian-inspired shearling coat," chimed Canadian fashion journalist Jeanne Beker.
Sanctuary President Sherri Delaney said he would be paired up with a "motherly" monkey and get some company when two female rhesus monkeys arrive in the coming weeks at the sanctuary, which currently holds 22 primates.
She said he won't be seeing his double-breasted shearling coat anytime soon as he becomes acclimatized to living more naturally with his fellow monkeys.
Animal services spokeswoman Mary Lou Leiher said Darwin was in good shape after being captured.
"He's a baby. He's a little bit sensitive," Leiher told reporters Monday.
Leiher said it was a "stressful time" for Darwin, adding he was "very quiet" and didn't show any signs of personality during his time in the north Toronto shelter.
"A lot of people who get these types of pets don't understand what kind of care they need," she said.
The owners of the Montreal-born monkey — whose identities have not been made public — have been fined $240 for breaking the city's prohibited-animal bylaw, said Leiher.
She stressed that there are good reasons for keeping exotic creatures like the pint-sized monkey outlawed.
"It's not appropriate to keep an animal like this as a pet, especially in a city where he's obviously gotten loose and (is) roaming around in a parking lot by himself in public," Leiher said.
"The bylaw is in place to protect the safety of the public as well as the safety and health of the animal," she added.
Darwin was being examined for any injuries or viruses he may carry, she said, noting the rhesus species is capable of carrying the Herpes B virus, which can be transferred to humans.
Greg Tarry, a manager with the Canadian Association of Zoos and Aquariums, said monkeys may be small and cute when they're young, but that keeping one as a pet can be dangerous as the creature grows older and more assertive.
"You start getting into competitions about 'who's in charge here,' and then the animal becomes aggressive," he said.
"And if that happens you've got an animal without social skills unable to live in a society of primates who's too aggressive to live with people."
"You've basically got an animal with no future at all," said Tarry, a former head of animal care at the Calgary Zoo.