These identical objects look exactly like wedding rings, with golden bands and a single diamond. When a single humanoid puts on one of the rings, nothing happens. The rings are only usable when both rings are worn by two different humanoids

Once the rings are active, they cannot be removed unless the wearer dies, or someone casts remove curse spell, which renders the rings useless.

While both rings are worn by two creatures, they always know the general location of the other wearer and can teleport to them once every d4 days

While both rings are worn, the creatures have a shared health pool, meaning that the health total of both creatures is combined and their souls are linked. When one creature takes damage, the damage total is split evenly between the two creatures. When the shared health is depleted, both creatures must roll their death saving throws separately. Once one of the creature pass their saving throws, they may make a medicine check (DC 19) to revive their partner

When one of the creatures takes a long rest, they only heal their class level's worth of health to the shared total.

Notes: When both rings are worn by two separate individuals, they magically attach themselves to the wearers and they cannot be removed until one or both of the the wearers die or the finger is removed