Throught the eyes of Denji we experience the world of Chainsaw Man, and the laws that rule it

We learn about the Concept of Contracts, were a human can offer an aspect of themselves(including ALL of themselves) to a Devil in exchange for a favor in the capacity of the Devil's abilities if both participants agree to the terms of the contract. This usually results in the Devil letting the human have a fraction of the Devil's power on their control as per the contract, but the service offered by the Devil can be things outside of just giving powers, Contracts then being just a way to bind two individuals to an agreement

We see a lot of examples of contracts just on Part 1 alone, Aki can summon the Fox Devil's head by letting him eat some of his skin, Santa Claus contracts with the Darkness devilto obtain a fraction of it's power. there are some examples where these contracts are made with good itentiosn in mind, where a person sacrifices themselves in order to help others, Denji gives poochita some of his blood so both can live, Himeno gives the Ghost devil all of her so Aki could live, Aki offers Makima making a deal with any devil in exchange for keeping his new found family safe and happy

Contracts are based on agreement, on promises, on the idea of voluntarely giving a part of you to obtain something of your desire or need
And that's why Makima, the Control Devil is such a menace on this world. Since she overrides people's individuality of choice, she breaks the meaning of Contracts being a consented agreement between two parties

Makima is the rule breaker of the laws of this world, someone who can choose to ignore the nature of the universe itself, she ain't different from the idea of a God not being limited by the same rules of nature as mortals do. When the world's currency is consent, she manufactures said consent via her position as the Control Devil