The two are currently staying in the same hotel in Toronto, and an eyewitness tells ET they totally "looked like a new high school couple."
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The eyewitness shared that Joe and Gigi had dinner at restaurant Brassaii and later took a cab back to their hotel.
But wait, there's more! Earlier in the day, they also had brunch together at SOHO House. Joe, 25, reportedly seemed very comfortable with 20-year-old Gigi, and while they were careful not to show off too much public affection, they were nevertheless spotted playfully poking one another and appeared to be very flirty.
The Swimsuit Illustrated model was spotted wearing a black shirt, white blazer and jeans while out and about with the former Disney star. Earlier in the day, while attending the Maybelline 100th anniversary party, a solo Gigi wore the same white blazer -- without a shirt underneath -- and a pair of high-water white pants to match.
This is not the first time the duo has been spotted getting cozy. A source told Us Weekly that when they attended a CFDA Awards after party in the Boom Boom Room on Monday, they were "very close to each other and holding hands."
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And let's not forget they were also seen pet shopping and having lunch together in West Hollywood, Calif., back in May.
So are they or aren't they? Until either of them admits or denies it, you'll just have to just decide for yourself. But there's no question the couples in the video below are together! Watch now: