Fuelling those relationship rumours, they were later photographed hand-in-hand on a night out in West Hollywood and later at a celeb-fuelled 4th of July party.
Despite being photographed and filmed, Mendes, 20, went on to deny reports the pair were an item in a fan recorded Q and A video.
Judging by the above video things have certainly changed since then it seems.
WATCH: Shawn Mendes denies rumours he is dating Camila Cabello
The "I Know What You Did Last Summer" collaborators were also recently spotted over the weekend pashing yet again at a cafe in San Francisco.
You can see those pics over at TMZ.
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