Since Susie had left her car at Justin's place, they left together, and then Susie suggested they stop for some late-night snacks at a 7-Eleven.
The pair was "messing around with each other a little flirtatiously per usual," and then Justin recalled Susie asking him to stop playing around.
"I was like, 'Oh, this tone seems a little bit different," Justin shared.
"In the back of my head, I was like, 'If you're serious, I'm serious.' That was kind of my mindset. I had always been testing the lines, and I wasn't sure if she would go for it. So, I didn't want to cross those boundaries."
Once the buddies returned to Justin's place, Susie and Justin finally decided to be honest with each other about their feelings.
"We had a really nice conversation, and I kinda just went for it," Justin revealed.
"I was like, 'Hey listen, I don't know where you stand on our friendship or relationship. Obviously, I respect you so much, and I appreciate our friendship. But I'd be lying if I [said I] haven't thought about if there is potential for more than a friendship just given the natural chemistry that we had as friends.'"
Susie and Justin then ended up having their first kiss on his couch, which prompted a mutual decision to give a real relationship a shot.
However, the lovebirds agreed not to immediately share the news with their friend group, and so they dated in private for about three weeks.
Once Susie and Justin spilled the tea to their closest friends, they apparently still weren't ready to announce their relationship to the world.
In fact, Susie and Justin even flat out denied that they were dating -- and that they had ever hooked up -- during a December interview on the "Bachelor Happy Hour" podcast, which is co-hosted by Bachelor in Paradise couple Joe Amabile and Serena Pitt.
Susie and Justin were very especially playful and flirty during their interview, and they even seemed to hint that they were considering taking their dynamic out of the friend zone. But the pair claimed they didn't want to put their friendship at risk for a romance that may not work out in the long run.
Justin explained to E! News of their dishonesty, "We've always wanted to just kind of protect our privacy, which sounds funny to say because we went on the show where our romantic connections are far from private."
Justin elaborated, "But we wanted to just protect our peace, and control our narrative and not put any pressure on our relationship."
The couple even spent the holidays together, having their "own little hometown" date. Justin said he met Susie's family in Virginia and she met his family in Maryland, where the pair attended a Baltimore Ravens game.
Justin initially reached out to Susie via Instagram DMs when he needed a videographer for one of her work projects.
Justin also appeared on Bachelor in Paradise's eighth season in 2022.
While Justin had sparked a connection with Eliza Isichei, it didn't work out because she ultimately gave her rose to Rodney Mathews. When Eliza determined she had made a mistake and wanted Justin back, it was too late and he wasn't interested in reconciling.
"Justin dated people, I dated people," Susie shared of the couple's initial dynamic. "So the narrative of us being truly just friends was true."
Susie and the Bachelor in Paradise alum gushed to E! News about how they have a "natural, fun chemistry" and always have a blast together.
But Susie explained how their relationship goes much deeper than that, mainly because Justin provides her with unconditional acceptance and support.
"If I'm dealing with something, I just deal with it myself, and I don't know if I've ever felt like I could rely on someone to be there the way I can rely on Justin," Susie explained.
"It actually makes me kind of emotional talking about it because I feel like there have been so many things where he's just shown such good character when I've really needed somebody.... He's really shown up and been so supportive, and I've never had someone be there for me like that."
Susie added, "I have a great family, but like a partner, I've never had somebody show up the way he has."
Justin also praised Susie for being compassionate, patient and extremely loving.
"She's always just so understanding and kind, and she's a huge empath," Justin said.
"She's kind of taught me how to step back, and just communicate, and slow things down, and see things from a totally different angle, which is something that I probably needed."
In November 2023, Susie joked during an Instagram Q&A session how she was "trying" to move out of the friend zone with Justin after a summer romance she had fizzled out.
When asked directly if she was dating Andrew, Susie simply replied "no" during the August 1 episode of "The Viall Files" podcast.
And Andrew -- who had accompanied Susie to the Barbie movie premiere -- was also straight up asked if he was dating Susie during the podcast's July 25 episode.
"No, absolutely not. No," Andrew insisted, adding, "We're just going to completely deny it and deny it hard."
But Andrew boasted of Susie at the time, "Susie is the goofiest person you'll ever meet. I think she's the better version -- but girl version -- of me, where she doesn't really overthink the things that she does. She's just like, 'Hey, I'm going to do it.' And I think that's the coolest thing."
The podcast's co-hosts joked about how it looked like Susie was The Bachelorette star and she was trying to decide whether to give Andrew or Justin her final rose.
"We're basically on an ongoing two-on-one date right now," Andrew confirmed with a laugh.
"[Justin] did his video with her the other day on a Target run, and I don't know how I felt about it. But I try to support them, [even though] I wanted to be a part of the video."