Contract

Upon casting this spell, you manifest a magical parchment and quill both of which can levitate and be controlled telekinetically--for the purposes of writing on the parchment--by the caster. The parchment can only be written on using the quill created via the spell, both of which are indestructible to nearly all means save for direct divine intervention, a Wish spell, Dispel Magic, or being struck with the Disintegrate spell. All other sources of damage simply pass through the parchment and quill as if they were not there; striking anything behind said items.

With parchment and quill summoned, the caster may now begin to write the contents within, including the terms and conditions of the contract. The contract may be as long, short, complex, simple, or even verbose as you desire. The parchment will lengthen or shorten to accommodate the amount of writing on it. The parchment will always remain exactly 10 inches wide but has no maximum limit for its length--although it does have a minimum length limit of 12 inches.
Upon finishing the writing of the contract, you may then have up to 4 different beings--with a minimum Intelligence score of 6--sign it, including yourself. All participants must read the contract in its entirety, understand its contents upon signing it, and fully consent to signing it of their own volition. Participants under the effects of the Charmed condition are incapable of signing the contract and cannot wield the magic quill, be it physically or through some sort of magical or telekinetic means. They simply cannot interact with the quill whatsoever while Charmed. Upon being deliberated and signed by at least two different beings that meet the requirements, this spell may then be reactivated, at which point the contract is now in effect.
While this spell is in effect, all beings who signed the contract must follow it according to their understanding of its terms and conditions. These terms and conditions may vary drastically, from simple conditions to much more esoteric ones. Anything belonging to a signed participant may be included as part of the contract, be it a physical item or even something entirely metaphysical.

The contract may only be terminated or rendered void by specifying a way to do so within the terms and conditions of the contract, reaching the termination date, tampering with or destroying the contract via a Wish spell, or direct intervention by a god or being of comparable power and ability. Unless otherwise specified, contracts created via this spell will automatically be terminated after 1 month since activation.
Should a signed participant attempt to break the contract and no countermeasure or consequence is implemented via the contents of the contract, they will then by default take 6d4 psychic damage every hour that they continue violating the contract or until the contract is rendered void. During this time, they will suffer a persistent and intense migraine.
This contract is only capable of killing those who have signed it if, and only if, such a thing is specified within the contract.
Otherwise, the signed participants in question will simply be left at 1 hit point and will cease being damaged by the contract.

The contract cannot grant anything that at least one signed participant does not already own, be it some sort of physical object, ability, or even a metaphysical idea or emotion. In order for one party to be granted something via the signed contract, it must be traded from another signed party though not necessarily via equal exchange unless otherwise stated.

After having once taken effect, a contract created via this spell may then be temporarily paused for 1 hour, requiring the willful consent of every signed participant. During this time, signed participants may create amendments to the original contract but may never directly change, erase, contradict, obstruct, or nullify anything of the original written contract. Amendments themselves may be contradicted and overruled by new ones, as well as expanded upon, but not directly erased. All amendments must be signed by all previously-signed participants before taking effect.
Anything written on this contract will always be legible to the reader even if obstructed by a form of illusion or being rendered blind. It cannot be written on without the accompanying magic quill, which is dispelled upon the contract taking effect and cannot be summoned again until the contract is paused, during which the magic quill reappears and may be used to create amendments.

There is no limit to the number of contracts established by this spell that the caster may create or be involved in.

(The limits and ability of this spell may be edited and determined by the DM as much as they want. Please consult your DM before using this spell!)