The IC/OOC Divide and Metagaming
Most people who play roleplaying games are familiar with the divide between IC and OOC. We usually talk about this by saying things like, "Don't get mad if something happens to your character; your character is not you." It also leads to many players discouraging "metagaming," a blanket term that covers everything from "portraying a character as having knowledge that comes from outside the game" to "making decisions based on what the player wants instead of what the character would naturally do."
This strict division between IC and OOC suits some game systems well, but Rosette calls for a more nuanced approach. Rosette is story-focused and collaborative: it's a system in which the players don't just portray their characters, they also work together to tell a good story. Sometimes this means that players should act according to their own motivations, even when it goes against what their characters want.
We can see a simple example of this when players narrate the results of their characters being hit by an Attack, and the concept is particularly important when negotiating Goals and Consequences during Conflicts.
Attack Results
When your character is hit by an Attack, you (the player) decide what that hit means. If you take Stress, you narrate what happens to your character that advances the Consequence of the Conflict; if you take an Affliction instead, you narrate how your character is affected in a way that doesn't advance the Consequence but does leave them vulnerable to later Attacks.
This is an OOC decision. Obviously your character wouldn't want to burst into tears, get outsmarted, or become injured. But you as a player have the opportunity to depict the effects of an Attack in a way that highlights your character and makes the story more interesting. Getting stymied or hurt is bad for your character, but it's good for you as a player.
The effects of a successful Attack don't need to match what the attacker intended. If someone succeeds on an Attack to convince your character to take a bad business deal, that doesn't mean you must have them ruin their own company. Instead, maybe they lose face when their accountant has to veto the deal, or they liquidate a bunch of stock at a bad time in preparation for a deal that (by the end of the Conflict) will end up falling through. Likewise, if someone succeeds at shooting you with a gun, your character could become injured, but they could instead dive into a filthy dumpster or cower behind cover while frantically shouting the information they were trying to keep away from the shooter.
You don't pick which one of these results your character would prefer. You pick which one is most interesting to you as a player. This might even depend on information your character doesn't know! Taking Stress could mean that your character unknowingly picks up the locked briefcase containing evidence that could exonerate them... as long as it's not found in their possession.
This approach—where you make decisions as a player that your character wouldn't make on their own—is especially important in Conflict negotiation.
Conflict Negotiation
At the start of each Conflict scene, the players discuss the Goals and Consequences at stake. If the players incapacitate their opponent, they achieve their Goal and avoid the Consequences of failure; if the player characters are incapacitated, they suffer the Consequences and do not achieve their Goal.
This is part of the consent culture of Rosette. Having the risk of negative outcomes helps produce tension, but you only suffer the outcomes that you are willing to see. If you don't want your character to risk death, they won't. If you don't want to be responsible for letting a murderer escape justice, you don't have to. But this decision is made by you as a player, not your character.
The Consequence that the players choose for a Conflict should be something that your characters' don't want to see happen. That's what makes it provide interesting tension and serve as a motivation to act against. Your ability to choose a Consequence isn't there so that you can avoid bad things happening to your character; it's there so that you can make sure the right bad things happen for your character's development.
Ideally, you as a player should feel that the story is equally well-served by either the Goal or the Consequence occurring. Your character might not want to face a tragedy, but tragic stories are a good way to explore a character's nature and provide them with a way to shine.
And beyond that, your role in Rosette isn't just to portray your character. It's to work together with the other players to create an ongoing story that provides a satisfying effect overall and gives each character an opportunity to be interesting. Sometimes that will mean choosing a Consequence that doesn't work perfectly for your character or pursuing a Goal as a group that your character doesn't really care about. You should still seek consensus and not just compromise, but consensus sometimes means valuing the group you're in as well as your individual priorities.
Metagaming Is Okay
One of the basic principles of Rosette Diceless is to "Only do what makes sense in the story." This means that your character's actions should make sense from that character's perspective, yes. But it also means that sometimes you should make a choice that would seem arbitrary to your character because you as a player know that it will serve the story.
You are not your character. You are often your character's advocate, but sometimes you're their unseen antagonist, putting challenges and obstacles in their way to highlight and explore their strengths and weaknesses. Don't be afraid to do things that your character won't like. It's for their own good.