While "Grand Theft Auto VI" places the relationship between Jason and Lucia at the core of its narrative, Rockstar Games has no intention of forcing players into a romantic storyline.
Rob Nelson, Head of Development and Co-Studio Head at Rockstar North, told IGN, “I would say that if you like that concept, it’s going to be great. If you’re not interested, then don’t touch it. It’s all up to you.”
He elaborated, “The narrative structure itself is designed so that their circumstances will force them to be together and collaborate for most of the story. At the very least, they’ll spend most events together as criminal partners.”

Nelson further stated, “I don’t want to say too much more because I don’t want to spoil anything. It really adds a compelling element to the whole thing, and it’s one of the reasons we wanted to try this type of story—because for us, it’s something completely different.” He continued, “If players are willing to invest in it, can we add some kind of emotional resonance to 'GTA'? At the same time, if players aren’t interested at all, can we provide mechanisms for them to opt out directly? If they feel, ‘I don’t want to have a romance in this game,’ that’s what we want to know. We don’t want to force it upon players.”
Should players choose to cultivate the relationship, the duo can engage in various activities together, including robberies, exploring locations, holding hands, visiting zoos, studying animals, scuba diving, skydiving, strolling on beaches, and canoeing.
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“When you bring them together, you get a sense that you’re nurturing this relationship, and you start to protect them as a whole. This wasn’t an effect we knew would happen from the start; it’s something we discovered along the way,” Nelson explained. “Whether it’s getting into trouble together, escaping the police, getting into a car, or waiting for the other person, operating them together is really great. You get a feeling that you’re taking care of them—of course, assuming you enjoy that.”
via: IGN