Agreed that things like governments and corporations are made up ideas, but ideas need to be properly defined so we know what we're communicating.

You asked if a government in your society doesn't exist what is the agreed upon legal code?

You're asking the wrong question. When I say that I'm against government, what I mean is I am against the idea that I can be born into an agreement and made to suffer that system. I was born and continue to live in the US, but I did not agree to give the government tens of thousands of dollars annually, which they take without my consent. I argue that all government is, fundamentally, is a relative force monopoly. If say, the drug cartels in Mexico can simply do what they wish and the Mexican government can't stop them, then the actual government in Mexico are the drug cartels, not the Mexican government. Saying it's not is just not properly defining what government is.

In a government where there's freedom for all there would be two systems in place to define what is legal. One would be logic. It's simply immoral to murder (not kill, murder), steal, rape, defraud, or assault. You cannot do those things and free people understand that even if a relative force monopoly makes a "law" saying you can, that doesn't legitimize it, and you are well within your right, as given by nobody at all, to seek out and use violence against those who would commit those acts, regardless of what the "law" said.

If it were legal in the US to rape, would you rape? Would you allow another to rape if you had the power to stop them? Would you stop someone who tried to rape your child? Who cares what the law says?

We already realize that law does not correlate to right and wrong.

The second aspect of law would be that in which is consented to, but that depends entirely on who owns what, and I don't mean arbitrarily owns what, but objectively (logically) owns what.

You can logically work out what is owned and what is stolen. It isn't difficult.

And to own a thing means you hold exclusive authority over it. If I hold exclusive authority over my house for instance, then it doesn't matter what other people agree to, or turn into "law", you never hold authority over my house. If you do, then you are stealing my authority over my house from me, which is theft. If you use theft, I am authorized to use violence against you to stop your theft.

So it doesn't matter how many people you have who agree to something if it pertains to violating my consent over my property. A million people can all vote and agree to kick me out of my house, and you'll succeed if you use violence against me, but both logically and philosophically, I would be well within my right to use even deadly force to stop any thugs you send to me to do so.

A "just" law is only one where you are protecting the will of others within a logical order of operations.

Now that being said! You CAN hold agreements between owners of property. Maybe 50 people in a region all agree to buy all of the neighboring roads, and they each agree to put fourth 5% of their income per year to do so. Maybe they all agree this will be a "law", and they agree upon a punishment that can be enacted if someone doesn't do this. NOW what you have is a situation where you CAN use violence against someone who goes against the agreement because we're not talking about the group violating the consent of the individual, we're talking about the individual engaging in an action of which violated a preexisting will of the group.

Another question you had:

"Can you guarantee everyone in your society, which you’ve argued can be over 250 people, will agree on a singular legal code without some kind of government with a legislative branch?"

You don't need to. If everyone in my "society" want to make a rule saying you can remove Joe from his home, all you're doing is banding together to do a sinister deed. That is a corrupt society to begin with, and an authoritarian one.

You don't and can't agree to do something with someone else's property, because it isn't yours. This is like saying that your neighbor, Tony, has some kind of right to your car because he lives next door. That's absurd. You and only you can decide what happens to your car unless what you want to do directly violates Tony's rights over his will. For example, I can't drive it into his house and set it on fire because I would need to have initiated an action of which violated Tony's will, so I can't do that.

Now if Tony and I both got together and CONSENTED to go 50/50 on a new car, it's up to us and us alone to set the "law" on who can make utility of that car, or who can destroy it, sell it, who gets what if we agree to sell it, who maintains it, puts gas in it, etc.

You don't get to come along and make demands of Tony and I regarding our car. It's ours, nor yours. Leave us alone and stop trying to dictate the choices of others.

The problem with your line of questioning - and I mean with with respect, truly - is that you're thinking about all of this in this scope of the concept of "public property". There is no such thing. There is property, full stop. The idea of "public property" is a blatant misnomer. Think of it like this:

Menards owns a lawn mower and they agree to sell it to me. It's my lawn mower. It's mine because Menards did not steal anything from anyone else to make it, my will was aligned to own it and the will of those who consented to the system that is Menards hold a will to accept selling it to me, and because what I traded for it was mine as I did not steal the money I traded for it.

But if Tony next door again comes to my home with a baseball bat and tells me I am now going to give him $500 towards a lawn mower, and it will be in the best interest of the neighborhood because 9 other people all got together and agreed it was, and thus, it isn't theft what Tony is doing, Tony is just lying - it's just theft.

You can't "legitimize" theft by wearing a badge or saying you come from some official sounding group name. Other people agreeing to rape you doesn't legitimize rape any more than other people agreeing to rob you legitimizes theft. Is this making sense?

But again, if Tony and I both consent to buy a lawn mower together, then we are both consensual property owners of that lawn mower and nobody else can tell us what to do with it.

So your other two questions here aren't the right questions to ask either:

"How do they even go about figuring out the legal code without some organization?" - and - "If they do agree on a legal code, who are the people spending time on maintaining and updating the code and how are they paid?"

Nobody ever said there wouldn't be organization, or even violence. There could still be police, firefighters, teachers, engineers, and everything else that governments tend to monopolize or "provide".

Who sets the laws for the roads? Well, which roads? Who owns the roads? Do I own the road leading to my home? Do Tony and I own it? Did all 50 of us who live in that area get together and consent to all go in and buy the roads? Then the owners of those roads set the laws for those roads.

Maybe Tony and I own a little piece of road and the only law is we don't want you to go more than 40MPH while driving on it. Well there you go! And if you don't like our ruling about our property, key words there, OUR PROPERTY, then you don't need to use it.

I make the laws in my own home. If you don't like it, you're free to leave. In fact, if I asked you to leave and you flat out refused, I would just be warranted to use violence against you. If I couldn't get you to leave with violence even, then deadly force would be warranted. And yes, that would be warranted if it got to that serious of a situation.

But that's already how governments generally work today. If you come into my home and I ask you to leave and you refuse, I call the police and the police will use violence against you. What on earth do you think they do if you resist that violence? Play nice?

Your next question:

"How do you adjudicate this issue in your society? There’s no judicial branch of government."

However the property owners who have been faulted want. Maybe in my area we've set up a system for this. What is most likely is as a "formal", current government waned, this would open up avenues in the free market for people to offer these kinds of services. In fact, many judicial systems are already handled by courts not run by the government. Many kinds of issues even in the US are resolved by these kinds of courts because it's better than utilizing the government to do so, as governments tend to be more corrupt, very slow, and very poor quality in basically everything they do.

Maybe you have Amazon Justice, Microsoft Courts, and Elon Musk's Justice-X to choose from, and maybe the people in your area all consent to use a specific one so they agree to all go in and pay for those services. Maybe those small groups of people also get together with other small groups of people and form larger organizations who also agree on certain things. You can still have society without authoritarianism. The notion of, "whatever would we do if we don't let other people rob us and our neighbors to do things" is so absurd it makes my head spin.

I'm not saying no organization. I'm not saying no schools, no security, no military, no roads, etc. I'm saying NO MORE AUTHORITARIANISM. No more theft on a grand scale. No more telling me when I turned 18 that I had to sign up for a draft where if some old man decided I had to die oversees then I either did so or I'd be locked away. No more forcing me to days of being a juror without my consent, where the state would pay me pennies a day and I lost precious time with my family, my job, and my entire life.

There is no such thing as a social contract - not within the constrains of what it's depicted at as of current. That's all just authoritarian propaganda.