In GTA VI, the relationship between Jason and Lucia can be shaped by player choices. Rob Nelson from Rockstar North stated that the two will always cooperate and look out for each other, but players can choose to develop a romantic relationship or maintain their partnership as criminal accomplices; how this relationship is managed will influence the story's progression.
Nelson stated that the team wants players who choose to invest in this relationship to have an emotional experience, while also leaving room for those who do not wish to engage with romantic content. Whether the two become intimate will not provide any specific gameplay benefits.
The game features a standalone relationship system, separate from the system that records the types of criminal activities players commit. Shared activities between Jason and Lucia, such as kayaking, playing mini-golf, or robbing stores, can positively impact their relationship.
Regarding physical intimacy, Nelson considers it an important part of the relationship but did not specify how the game will present it in detail. He only stated that the team needs to experiment repeatedly to find the right approach. The game's rating information involves nudity, intense sexual content, or sexual scenes, but there are currently no signs of interactive sex scenes, and the specific presentation remains unrevealed.