The pair weren't shy in having their arms around one another while walking together around the event, even mingling with Riverdale co-star Camila Mendes at times.
KJ Apa and Britt Robertson met when they acted together in the 2017 movie A Dog's Purpose.
Now, they are set to star together as love interests in their new film I Still Believe, which is a sequel to the 2018 movie I Can Only Imagine.
The New Zealand born actor will play a real-life Christian music singer called Jeremy Camp, with Britt starring as his wife Melissa Henning.
The movie will also feature country-pop singer Shania Twain, set for release in 2020.
One of the biggest telltale signs of the two actors being together is the fact that Britt Robertson is not set to appear in any Comic Con panels, with KJ joining his Riverdale co-stars for their event.
Supportive girlfriend, yes?
In July 2017, KJ Apa expressed his infatuation with Britt Robertson, after working together on A Dog's Purpose.
Speaking to Stuff.co.nz about working together, KJ revealed that, "She was amazing. She was great.
"Obviously you're there for three months, and you don't really have anyone else to hang with, so we were hanging out a lot.
"That's kind of the other thing I learned, you're on these projects and you meet these people and you get really close with them and then you never really see them probably for the rest of your life."
At the time, Britt was dating Maze Runner and Teen Wolf star Dylan O'Brien. The pair were linked from 2012 until late 2018.
As for KJ Apa's love life, it has been a complete mystery. Aside from being linked to a then-16-year-old girl named Corinne Isherwood in January 2018, KJ has kept his dating life completely under wraps.
Speaking to Cosmopolitan in 2017, he revealed, "I think I'm just waiting for the right time, right girl," he says. "I'm pretty busy at the moment. I don't know how much I have to offer to someone right now."
The following year, he told Seventeen, "The thing is, I don't think it matters whether you're looking for a relationship or not. It's not for us to decide when we meet the love of our lives."
What do you guys think about this new celeb pairing?!
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