On Wednesday, Daddario shared a photo of herself wearing an off-the-shoulder animal print Zac Posen gown, which she wore to the premiere of Rampage later that evening.
In the Instagram snap, the star, 32, is pictured in her home as she and her dog adorably stared into each other’s eyes.
Her fans were quick to make remarks about her beauty, but they were not the only ones, with Efron cheekily commenting, “Two hot bitches.”
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The former Baywatch costars have been rather coy about their romance but a source tells People that the pair has been seeing each other “on and off since their time working together on the movie last year, but they are not officially dating.”
Last week, Efron, 30, and Daddario, 32, were spotted doing some shopping for their dogs at a Los Angeles pet store. After browsing the aisles together, Efron helped the actress load supplies into the trunk of a white SUV.
Back in May, Daddario addressed rumors that the two were dating, telling E!, “We work together closely; he’s my love interest in the film. I understand why people would go crazy over something like that, but Zac and I are very good friends.”
She then joked, “We would have very blue-eyed children, wouldn’t we?”
For Daddario’s 32nd birthday last month, Efron took to social media, posting a gushing tribute to the actress.
“Happy birthday to one of the the most real, down to 🌎, stunning, intelligent, creative, loving, and most rare Pokémon ever created #alexdaddario,” he wrote along with a pic of the two.