Promise

Level: 8th
Casting Time: 1 Action
Range: Touch
Components: V,S
Duration: 10 Years
School: Enchantment
Description: You touch one creature, and it makes a promise. If the creature refuses to make a promise, refuses or can't speak, or is incapable of making promises the spell has no effect and instantly fails.
If the target makes a promise, that promise becomes bond. Whether it be to keep a secret, or pick up the groceries within a time frame, they are bonded to it.
For the duration, if for any reason the target breaks their promise they instantly take 12d12 necrotic damage. If this damage would reduce them to 0 hit points, they instantly die and rise again as a hostile Deathlock.